Scalable Vector Graphics (SVG) 1.1 (Друга редакція)

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
document event атрибути — ‘onunload’, ‘onabort’, ‘onerror’, ‘onresize’, ‘onscroll’, ‘onzoom’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘x’
‘y’
‘width’
‘height’
‘viewBox’
‘preserveAspectRatio’
‘zoomAndPan’
‘version’
‘baseProfile’
‘contentScriptType’
‘contentStyleType’
‘x’
‘y’
‘width’
‘height’
‘version’
‘baseProfile’

DOM Інтерфейсs:

SVGSVGElement

Attribute definitions:

version = "<number>"

Indicates the SVG language version to which this document fragment conforms.
In SVG 1.0 [SVG10], this атрибут was fixed to the value '1.0'. For SVG 1.1, the атрибут should have the value '1.1'.
Animatable: no.

baseProfile = profile-name

Describes the minimum SVG language profile that the author believes is necessary to correctly render the content. The атрибут does not specify any processing restrictions; It can be considered metadata. For example, the value of the атрибут could be used by an authoring tool to warn the user when they are modifying the document beyond the scope of the specified base profile. Each SVG profile should define the text that is appropriate for this атрибут.
If the атрибут is not specified, the effect is as if a value of 'none' were specified.
Animatable: no.

x = "<coordinate>"

(Has no meaning or effect on outermost svg елементи.)
The x-axis coordinate of one corner of the rectangular region into which an embedded ‘svg’ елемент is placed.
If the атрибут is not specified, the effect is as if a value of '0' were specified.
Animatable: yes.

y = "<coordinate>"

(Has no meaning or effect on outermost svg елементи.)
The y-axis coordinate of one corner of the rectangular region into which an embedded ‘svg’ елемент is placed.
If the атрибут is not specified, the effect is as if a value of '0' were specified.
Animatable: yes.

width = "<length>"

For outermost svg елементи, the intrinsic width of the SVG document fragment. For embedded ‘svg’ елементи, the width of the rectangular region into which the ‘svg’ елемент is placed.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
If the атрибут is not specified, the effect is as if a value of '100%' were specified.
Animatable: yes.

height = "<length>"

For outermost svg елементи, the intrinsic height of the SVG document fragment. For embedded ‘svg’ елементи, the height of the rectangular region into which the ‘svg’ елемент is placed.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
If the атрибут is not specified, the effect is as if a value of '100%' were specified.
Animatable: yes.

preserveAspectRatio = "[defer] <align> [<meetOrSlice>]"

View this example as SVG (SVG-enabled browsers only)

If the атрибут is not specified, then the effect is as if a value of 'xMidYMid meet' were specified.

Animatable: yes.

contentScriptType = "content-type"

See 'contentScriptType'.

contentStyleType = "content-type"

See 'contentStyleType'.

zoomAndPan = "disable | magnify"

See 'zoomAndPan'.

If an SVG document is likely to be referenced as a component of another document, the author will often want to include a ‘viewBox’ атрибут on the outermost svg елемент of the referenced document. This атрибут provides a convenient way to design SVG documents to scale-to-fit into an arbitrary viewport.

5.2 Grouping: the ‘g’ елемент

5.2.1 Огляд

The ‘g’ елемент is a container елемент for grouping together related graphics елементи.

Grouping constructs, when used in conjunction with the ‘desc’ and ‘title’ елементи, provide information about document structure and semantics. Documents that are rich in structure may be rendered graphically, as speech, or as braille, and thus promote accessibility.

A group of елементи, as well as individual objects, can be given a name using the ‘id’ атрибут. Named групи are needed for several purposes such as animation and re-usable objects.

An example:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg"
     version="1.1" width="5cm" height="5cm">
  <desc>Two групи, each of two rectangles</desc>
  <g id="group1" fill="red">
    <rect x="1cm" y="1cm" width="1cm" height="1cm"/>
    <rect x="3cm" y="1cm" width="1cm" height="1cm"/>
  </g>
  <g id="group2" fill="blue">
    <rect x="1cm" y="3cm" width="1cm" height="1cm"/>
    <rect x="3cm" y="3cm" width="1cm" height="1cm"/>
  </g>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x=".01cm" y=".01cm" width="4.98cm" height="4.98cm"
        fill="none" stroke="blue" stroke-width=".02cm"/>
</svg>

A ‘g’ елемент can contain other ‘g’ елементи nested within it, to an arbitrary depth. Thus, the following is possible:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg"
     version="1.1" width="4in" height="3in">
  <desc>Groups can nest</desc>
  <g>
     <g>
       <g>
       </g>
     </g>
   </g>
</svg>

Any елемент that is not contained within a ‘g’ is treated (at least conceptually) as if it were in its own group.

5.2.2 The ‘g’ елемент

‘g’

Categories:

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’

DOM Інтерфейсs:

SVGGElement

5.3 Визначення content for reuse, and the ‘defs’ елемент

5.3.1 Огляд

SVG allows graphical objects to be defined for later reuse. To do this, it makes extensive use of IRI references [RFC3987] to these other objects. For example, to fill a rectangle with a linear gradient, you first define a ‘linearGradient’ елемент and give it an ID, as in:

<linearGradient id="MyGradient">...</linearGradient>

You then reference the linear gradient as the value of the ‘fill’ властивість for the rectangle, as in:

<rect style="fill:url(#MyGradient)"/>

Some types of елемент, such as gradients, will not by themselves produce a graphical result. They can therefore be placed anywhere convenient. Якever, sometimes it is desired to define a graphical object and prevent it from being directly rendered. it is only there to be referenced elsewhere. To do this, and to allow convenient grouping defined content, SVG provides the ‘defs’ елемент.

It is recommended that, wherever possible, referenced елементи be defined inside of a ‘defs’ елемент. Among the елементи that are always referenced: ‘altGlyphDef’, ‘clipPath’, ‘cursor’, ‘filter’, ‘linearGradient’, ‘marker’, ‘mask’, ‘pattern’, ‘radialGradient’ and ‘symbol’. Визначення these елементи inside of a ‘defs’ елемент promotes understandability of the SVG content and thus promotes accessibility.

5.3.2 The ‘defs’ елемент

‘defs’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’

DOM Інтерфейсs:

SVGDefsElement

The ‘defs’ елемент is a container елемент for referenced елементи. For understandability and accessibility reasons, it is recommended that, whenever possible, referenced елементи be defined inside of a ‘defs’.

The content модель for ‘defs’ is the same as for the ‘g’ елемент; thus, any елемент that can be a child of a ‘g’ can also be a child of a ‘defs’, and vice versa.

Elements that are descendants of a ‘defs’ are not rendered directly; they are prevented from becoming part of the rendering tree just as if the ‘defs’ елемент were a ‘g’ елемент and the ‘display’ властивість were set to none. Note, however, that the descendants of a ‘defs’ are always present in the source tree and thus can always be referenced by other елементи; thus, the value of the ‘display’ властивість on the ‘defs’ елемент or any of its descendants does not prevent those елементи from being referenced by other елементи.

To provide some SVG user agents with an opportunity to implement efficient implementations in streaming environments, creators of SVG content are encouraged to place all елементи which are targets of local IRI references within a ‘defs’ елемент which is a direct child of one of the ancestors of the referencing елемент. For example:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="8cm" height="3cm"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Local URI references within ancestor's 'defs' елемент.</desc>
  <defs>
    <linearGradient id="Gradient01">
      <stop offset="20%" stop-color="#39F" />
      <stop offset="90%" stop-color="#F3F" />
    </linearGradient>
  </defs>
  <rect x="1cm" y="1cm" width="6cm" height="1cm" 
        fill="url(#Gradient01)"  />

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x=".01cm" y=".01cm" width="7.98cm" height="2.98cm"
        fill="none" stroke="blue" stroke-width=".02cm" />

</svg>

In the document above, the linear gradient is defined within a ‘defs’ елемент which is the direct child of the ‘svg’ елемент, which in turn is an ancestor of the ‘rect’ елемент which references the linear gradient. Thus, the above document conforms to the guideline.

5.4 The ‘desc’ and ‘title’ елементи

‘desc’

Categories:

Descriptive елемент

Content модель:

Any елементи or character data.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
‘class’
‘style’

DOM Інтерфейсs:

SVGDescElement

‘title’

Categories:

Descriptive елемент

Content модель:

Any елементи or character data.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
‘class’
‘style’

DOM Інтерфейсs:

SVGTitleElement

Each container елемент or graphics елемент in an SVG drawing can supply a ‘desc’ and/or a ‘title’ description string where the description is text-only. When the current SVG document fragment is rendered as SVG on visual media, ‘desc’ and ‘title’ елементи are not rendered as part of the graphics. User agents may, however, for example, display the ‘title’ елемент as a tooltip, as the pointing device moves over particular елементи. Alternate presentations are possible, both visual and aural, which display the ‘desc’ and ‘title’ елементи but do not display ‘path’ елементи or other graphics елементи. This is readily achieved by using a different (perhaps user) style sheet. For deep hierarchies, and for following ‘use’ елемент references, it is sometimes desirable to allow the user to control how deep they drill down into descriptive text.

In conforming SVG document fragments, any ‘title’ елемент should be the first child елемент of its parent. Note that those implementations that do use ‘title’ to display a tooltip often will only do so if the ‘title’ is indeed the first child елемент of its parent.

The following is an example. In typical operation, the SVG user agent would not render the ‘desc’ and ‘title’ елементи but would render the remaining contents of the ‘g’ елемент.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg SYSTEM "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg"
     version="1.1" width="4in" height="3in">
  <g>
    <title>Company sales by region</title>
    <desc>
      This is a bar chart which shows 
      company sales by region.
    </desc>
    <!-- Bar chart defined as vector data -->
  </g>
</svg>

Description and title елементи can contain marked-up text from other namespaces. Here is an example:

<?xml version="1.0" standalone="yes"?>
<svg xmlns="http://www.w3.org/2000/svg"
     version="1.1" width="4in" height="3in">
  <desc xmlns:mydoc="http://example.org/mydoc">
    <mydoc:title>This is an example SVG file</mydoc:title>
    <mydoc:para>The global description uses markup from the 
      <mydoc:emph>mydoc</mydoc:emph> namespace.</mydoc:para>
  </desc>
  <g>
    <!-- the picture goes here -->
  </g>
</svg>

Authors should always provide a ‘title’ child елемент to the outermost svg елемент within a stand-alone SVG document. The ‘title’ child елемент to an ‘svg’ елемент serves the purposes of identifying the content of the given SVG document fragment. Since users often consult documents out of context, authors should provide context-rich titles. Thus, instead of a title such as "Вступ", which doesn't provide much contextual background, authors should supply a title such as "Вступ to Medieval Bee-Keeping" instead. For reasons of accessibility, user agents should always make the content of the ‘title’ child елемент to the outermost svg елемент available to users. The mechanism for doing so depends on the user agent (e.g., as a caption, spoken).

The DTD definitions of many of SVG's елементи (particularly, container and text елементи) place no restriction on the placement or number of the ‘desc’ and ‘title’ sub-елементи. This flexibility is only present so that there will be a consistent content модель for container елементи, because some container елементи in SVG allow for mixed content, and because the mixed content rules for XML ([XML10], section 3.2.2) do not permit the desired restrictions. Representations of future versions of the SVG language might use more expressive representations than DTDs which allow for more restrictive mixed content rules. It is strongly recommended that at most one ‘desc’ and at most one ‘title’ елемент appear as a child of any particular елемент, and that these елементи appear before any other child елементи (except possibly ‘metadata’ елементи) or character data content. If user agents need to choose among multiple ‘desc’ or ‘title’ елементи for processing (e.g., to decide which string to use for a tooltip), the user agent shall choose the first one.

5.5 The ‘symbol’ елемент

‘symbol’

Categories:

Graphics елемент, graphics referencing елемент, structural елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘preserveAspectRatio’
‘viewBox’

DOM Інтерфейсs:

SVGSymbolElement

The ‘symbol’ елемент is used to define graphical template objects which can be instantiated by a ‘use’ елемент.

The use of ‘symbol’ елементи for graphics that are used multiple times in the same document adds structure and semantics. Documents that are rich in structure may be rendered graphically, as speech, or as braille, and thus promote accessibility.

The key distinctions between a ‘symbol’ and a ‘g’ are:

A ‘symbol’ елемент itself is not rendered. Only instances of a ‘symbol’ елемент (i.e., a reference to a ‘symbol’ by a ‘use’ елемент) are rendered.
A ‘symbol’ елемент has атрибути ‘viewBox’ and ‘preserveAspectRatio’ which allow a ‘symbol’ to scale-to-fit within a rectangular viewport defined by the referencing ‘use’ елемент.

Closely related to the ‘symbol’ елемент are the ‘marker’ and ‘pattern’ елементи.

‘symbol’ елементи are never rendered directly; their only usage is as something that can be referenced using the ‘use’ елемент. The ‘display’ властивість does not apply to the ‘symbol’ елемент; thus, ‘symbol’ елементи are not directly rendered even if the ‘display’ властивість is set to a value other than none, and ‘symbol’ елементи are available for referencing even when the ‘display’ властивість on the ‘symbol’ елемент or any of its ancestors is set to none.

5.6 The ‘use’ елемент

‘use’

Categories:

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘x’
‘y’
‘width’
‘height’
‘xlink:href’

DOM Інтерфейсs:

SVGUseElement

Any ‘svg’, ‘symbol’, ‘g’, graphics елемент or other ‘use’ is potentially a template object that can be re-used (i.e., "instanced") in the SVG document via a ‘use’ елемент. The ‘use’ елемент references another елемент and indicates that the graphical contents of that елемент is included/drawn at that given point in the document.

Unlike ‘image’, the ‘use’ елемент cannot reference entire files.

The ‘use’ елемент has optional атрибути ‘x’, ‘y’, ‘width’ and ‘height’ which are used to map the graphical contents of the referenced елемент onto a rectangular region within the current coordinate system.

The effect of a ‘use’ елемент is as if the contents of the referenced елемент were deeply cloned into a separate non-exposed DOM tree which had the ‘use’ елемент as its parent and all of the ‘use’ елемент's ancestors as its higher-level ancestors. Because the cloned DOM tree is non-exposed, the SVG Document Object Model (DOM) only contains the ‘use’ елемент and its атрибути. The SVG DOM does not show the referenced елемент's contents as children of ‘use’ елемент.

For user agents that support Styling with CSS, the conceptual deep cloning of the referenced елемент into a non-exposed DOM tree also copies any властивість values resulting from the CSS cascade ([CSS2], chapter 6) on the referenced елемент and its contents. CSS2 selectors can be applied to the original (i.e., referenced) елементи because they are part of the formal document structure. CSS2 selectors cannot be applied to the (conceptually) cloned DOM tree because its contents are not part of the formal document structure.

Property inheritance, however, works as if the referenced елемент had been textually included as a deeply cloned child of the ‘use’ елемент. The referenced елемент inherits властивості from the ‘use’ елемент and the ‘use’ елемент's ancestors. An instance of a referenced елемент does not inherit властивості from the referenced елемент's original parents.

If event атрибути are assigned to referenced елементи, then the actual target for the event will be the SVGElementInstance object within the "instance tree" corresponding to the given referenced елемент.

The event handling for the non-exposed tree works as if the referenced елемент had been textually included as a deeply cloned child of the ‘use’ елемент, except that events are dispatched to the SVGElementInstance objects. The event's target and currentTarget атрибути are set to the SVGElementInstance that corresponds to the target and current target елементи in the referenced subtree. An event propagates through the exposed and non-exposed portions of the tree in the same manner as it would in the regular document tree: first going from the root елемент to the ‘use’ елемент and then through non-exposed tree елементи in the capture phase, followed by the target phase at the target of the event, then bubbling back through non-exposed tree to the use елемент and then back through regular tree to the root елемент in bubbling phase.

An елемент and all its corresponding SVGElementInstance objects share an event listener list. The currentTarget атрибут of the event can be used to determine through which object an event listener was invoked.

The behavior of the ‘visibility’ властивість conforms to this модель of властивість inheritance. Thus, specifying 'visibility:hidden' on a ‘use’ елемент does not guarantee that the referenced content will not be rendered. If the ‘use’ елемент specifies 'visibility:hidden' and the елемент it references specifies 'visibility:hidden' or 'visibility:inherit', then that one елемент will be hidden. Якever, if the referenced елемент instead specifies 'visibility:visible', then that елемент will be visible even if the ‘use’ елемент specifies 'visibility:hidden'.

Animations on a referenced елемент will cause the instances to also be animated.

A ‘use’ елемент has the same visual effect as if the ‘use’ елемент were replaced by the following generated content:

If the ‘use’ елемент references a ‘symbol’ елемент:

In the generated content, the ‘use’ will be replaced by ‘g’, where all атрибути from the ‘use’ елемент except for ‘x’, ‘y’, ‘width’, ‘height’ and ‘xlink:href’ are transferred to the generated ‘g’ елемент. An additional transformation translate(x,y) is appended to the end (i.e., right-side) of the ‘transform’ атрибут on the generated ‘g’, where x and y represent the values of the ‘x’ and ‘y’ атрибути on the ‘use’ елемент. The referenced ‘symbol’ and its contents are deep-cloned into the generated tree, with the exception that the ‘symbol’ is replaced by an ‘svg’. This generated ‘svg’ will always have explicit values for атрибути ‘width’ and ‘height’. If атрибути ‘width’ and/or ‘height’ are provided on the ‘use’ елемент, then these атрибути will be transferred to the generated ‘svg’. If атрибути ‘width’ and/or ‘height’ are not specified, the generated ‘svg’ елемент will use values of '100%' for these атрибути.
If the ‘use’ елемент references an ‘svg’ елемент:

In the generated content, the ‘use’ will be replaced by ‘g’, where all атрибути from the ‘use’ елемент except for ‘x’, ‘y’, ‘width’, ‘height’ and ‘xlink:href’ are transferred to the generated ‘g’ елемент. An additional transformation translate(x,y) is appended to the end (i.e., right-side) of the ‘transform’ атрибут on the generated ‘g’, where x and y represent the values of the ‘x’ and ‘y’ атрибути on the ‘use’ елемент. The referenced ‘svg’ and its contents are deep-cloned into the generated tree. If атрибути ‘width’ and/or ‘height’ are provided on the ‘use’ елемент, then these values will override the corresponding атрибути on the ‘svg’ in the generated tree.
Otherwise:

In the generated content, the ‘use’ will be replaced by ‘g’, where all атрибути from the ‘use’ елемент except for ‘x’, ‘y’, ‘width’, ‘height’ and ‘xlink:href’ are transferred to the generated ‘g’ елемент. An additional transformation translate(x,y) is appended to the end (i.e., right-side) of the ‘transform’ атрибут on the generated ‘g’, where x and y represent the values of the ‘x’ and ‘y’ атрибути on the ‘use’ елемент. The referenced object and its contents are deep-cloned into the generated tree.

For user agents that support Styling with CSS, the generated ‘g’ елемент carries along with it the "cascaded" властивість values on the ‘use’ елемент which result from the CSS cascade ([CSS2], chapter 6). Additionally, the copy (deep clone) of the referenced resource carries along with it the "cascaded" властивість values resulting from the CSS cascade on the original (i.e., referenced) елементи. Thus, the result of various CSS selectors in combination with the ‘class’ and ‘style’ атрибути are, in effect, replaced by the functional equivalent of a ‘style’ атрибут in the generated content which conveys the "cascaded" властивість values.

Example Use01 below has a simple ‘use’ on a ‘rect’.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 100 30" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <desc>Example Use01 - Simple case of 'use' on a 'rect'</desc>
  <defs>
    <rect id="MyRect" width="60" height="10"/>
  </defs>
  <rect x=".1" y=".1" width="99.8" height="29.8"
        fill="none" stroke="blue" stroke-width=".2" />
  <use x="20" y="10" xlink:href="#MyRect" />
</svg>

Example Use01

View this example as SVG (SVG-enabled browsers only)

The visual effect would be equivalent to the following document:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 100 30"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example Use01-GeneratedContent - Simple case of 'use' on a 'rect'</desc>
  <!-- 'defs' section left out -->

  <rect x=".1" y=".1" width="99.8" height="29.8"
        fill="none" stroke="blue" stroke-width=".2" />

  <!-- Start of generated content. Replaces 'use' -->
  <g transform="translate(20,10)">
    <rect width="60" height="10"/>
  </g>
  <!-- End of generated content -->

</svg>

View this example as SVG (SVG-enabled browsers only)

Example Use02 below has a ‘use’ on a ‘symbol’.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 100 30" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <desc>Example Use02 - 'use' on a 'symbol'</desc>
  <defs>
    <symbol id="MySymbol" viewBox="0 0 20 20">
      <desc>MySymbol - four rectangles in a grid</desc>
      <rect x="1" y="1" width="8" height="8"/>
      <rect x="11" y="1" width="8" height="8"/>
      <rect x="1" y="11" width="8" height="8"/>
      <rect x="11" y="11" width="8" height="8"/>
    </symbol>
  </defs>
  <rect x=".1" y=".1" width="99.8" height="29.8"
        fill="none" stroke="blue" stroke-width=".2" />
  <use x="45" y="10" width="10" height="10" 
       xlink:href="#MySymbol" />
</svg>

Example Use02

View this example as SVG (SVG-enabled browsers only)

The visual effect would be equivalent to the following document:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 100 30"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example Use02-GeneratedContent - 'use' on a 'symbol'</desc>

  <!-- 'defs' section left out -->

  <rect x=".1" y=".1" width="99.8" height="29.8"
        fill="none" stroke="blue" stroke-width=".2" />

  <!-- Start of generated content. Replaces 'use' -->
  <g transform="translate(45, 10)" >
    <!-- Start of referenced 'symbol'. 'symbol' replaced by 'svg',
         with x,y,width,height=0,0,100%,100% -->
    <svg width="10" height="10" 
         viewBox="0 0 20 20">
      <rect x="1" y="1" width="8" height="8"/>
      <rect x="11" y="1" width="8" height="8"/>
      <rect x="1" y="11" width="8" height="8"/>
      <rect x="11" y="11" width="8" height="8"/>
    </svg>
    <!-- End of referenced symbol -->
  </g>
  <!-- End of generated content -->

</svg>

View this example as SVG (SVG-enabled browsers only)

Example Use03 illustrates what happens when a ‘use’ has a ‘transform’ атрибут.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 100 30" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <desc>Example Use03 - 'use' with a 'transform' атрибут</desc>
  <defs>
    <rect id="MyRect" x="0" y="0" width="60" height="10"/>
  </defs>
  <rect x=".1" y=".1" width="99.8" height="29.8"
        fill="none" stroke="blue" stroke-width=".2" />
  <use xlink:href="#MyRect"
       transform="translate(20,2.5) rotate(10)" />
</svg>

Example Use03

View this example as SVG (SVG-enabled browsers only)

The visual effect would be equivalent to the following document:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 100 30"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example Use03-GeneratedContent - 'use' with a 'transform' атрибут</desc>

  <!-- 'defs' section left out -->

  <rect x=".1" y=".1" width="99.8" height="29.8"
        fill="none" stroke="blue" stroke-width=".2" />

  <!-- Start of generated content. Replaces 'use' -->
  <g transform="translate(20,2.5) rotate(10)">
    <rect x="0" y="0" width="60" height="10"/>
  </g>
  <!-- End of generated content -->

</svg>

View this example as SVG (SVG-enabled browsers only)

Example Use04 illustrates a ‘use’ елемент with various methods of applying CSS styling.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="3cm" viewBox="0 0 1200 300" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <desc>Example Use04 - 'use' with CSS styling</desc>
  <defs style=" /* rule 9 */ stroke-miterlimit: 10" >
    <path id="MyPath" d="M300 50 L900 50 L900 250 L300 250"
                     class="MyPathClass"
                     style=" /* rule 10 */ stroke-dasharray:300,100" />
  </defs>
  <style type="text/css">
    <![CDATA[
      /* rule 1 */ #MyUse { fill: blue }
      /* rule 2 */ #MyPath { stroke: red }
      /* rule 3 */ use { fill-opacity: .5 }
      /* rule 4 */ path { stroke-opacity: .5 }
      /* rule 5 */ .MyUseClass { stroke-linecap: round }
      /* rule 6 */ .MyPathClass { stroke-linejoin: bevel }
      /* rule 7 */ use > path { shape-rendering: optimizeQuality }
      /* rule 8 */ g > path { visibility: hidden }
    ]]>
  </style>

  <rect x="0" y="0" width="1200" height="300"
         style="fill:none; stroke:blue; stroke-width:3"/>
  <g style=" /* rule 11 */ stroke-width:40">
    <use id="MyUse" xlink:href="#MyPath" 
         class="MyUseClass"
         style="/* rule 12 */ stroke-dashoffset:50" />
  </g>
</svg>

Example Use04

View this example as SVG (SVG-enabled browsers only)

The visual effect would be equivalent to the following document. Observe that some of the style rules above apply to the generated content (i.e., rules 1-6, 10-12), whereas others do not (i.e., rules 7-9). The rules which do not affect the generated content are:

Rules 7 and 8: CSS selectors only apply to the formal document tree, not on the generated tree; thus, these selectors will not yield a match.
Rule 9: The generated tree only inherits from the ancestors of the ‘use’ елемент and does not inherit from the ancestors of the referenced елемент; thus, this rule does not affect the generated content.

In the generated content below, the selectors that yield a match have been transferred into inline ‘style’ атрибути for illustrative purposes.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="3cm" viewBox="0 0 1200 300"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example Use04-GeneratedContent - 'use' with a 'transform' атрибут</desc>

  <!-- 'style' and 'defs' sections left out -->

  <rect x="0" y="0" width="1200" height="300"
         style="fill:none; stroke:blue; stroke-width:3"/>
  <g style="/* rule 11 */ stroke-width:40">

    <!-- Start of generated content. Replaces 'use' -->
    <g style="/* rule 1 */ fill:blue;
                 /* rule 3 */ fill-opacity:.5;
                 /* rule 5 */ stroke-linecap:round;
                 /* rule 12 */ stroke-dashoffset:50" >
      <path d="M300 50 L900 50 L900 250 L300 250"
            style="/* rule 2 */ stroke:red; 
                   /* rule 4 */ stroke-opacity:.5; 
                   /* rule 6 */ stroke-linejoin: bevel; 
                   /* rule 10 */ stroke-dasharray:300,100" />
    </g> 
    <!-- End of generated content -->

  </g>
</svg>

View this example as SVG (SVG-enabled browsers only)

When a ‘use’ references another елемент which is another ‘use’ or whose content contains a ‘use’ елемент, then the deep cloning approach described above is recursive. Якever, a set of references that directly or indirectly reference a елемент to create a circular dependency is an error, as described in References and the ‘defs’ елемент.

Attribute definitions:

x = "<coordinate>": The x-axis coordinate of one corner of the rectangular region into which the referenced елемент is placed.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
y = "<coordinate>": The y-axis coordinate of one corner of the rectangular region into which the referenced елемент is placed.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
width = "<length>": The width of the rectangular region into which the referenced елемент is placed. A negative value is an error (see Error processing). A value of zero disables rendering of this елемент.
Animatable: yes.
height = "<length>": The height of the rectangular region into which the referenced елемент is placed. A negative value is an error (see Error processing). A value of zero disables rendering of this елемент.
Animatable: yes.
xlink:href = "<iri>": A IRI reference to an елемент/fragment within an SVG document.
Animatable: yes.

5.7 The ‘image’ елемент

‘image’

Categories:

Graphics елемент, graphics referencing елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘preserveAspectRatio’
‘transform’
‘x’
‘y’
‘width’
‘height’
‘xlink:href’

DOM Інтерфейсs:

SVGImageElement

The ‘image’ елемент indicates that the contents of a complete file are to be rendered into a given rectangle within the current user coordinate system. The ‘image’ елемент can refer to raster image files such as PNG or JPEG or to files with MIME type of "image/svg+xml". Conforming SVG viewers need to support at least PNG, JPEG and SVG format files.

The result of processing an ‘image’ is always a four-channel RGBA result. When an ‘image’ елемент references a raster image file such as PNG or JPEG files which only has three channels (RGB), then the effect is as if the object were converted into a 4-channel RGBA image with the alpha channel uniformly set to 1. For a single-channel raster image, the effect is as if the object were converted into a 4-channel RGBA image, where the single channel from the referenced object is used to compute the three color channels and the alpha channel is uniformly set to 1.

An ‘image’ елемент establishes a new viewport for the referenced file as described in Establishing a new viewport. The bounds for the new viewport are defined by атрибути ‘x’, ‘y’, ‘width’ and ‘height’. The placement and scaling of the referenced image are controlled by the ‘preserveAspectRatio’ атрибут on the ‘image’ елемент.

When an ‘image’ елемент references an SVG image, the ‘clip’ and ‘overflow’ властивості on the root елемент in the referenced SVG image are ignored (in the same manner as the ‘x’, ‘y’, ‘width’ and ‘height’ атрибути are ignored). Unless the value of ‘preserveAspectRatio’ on the ‘image’ елемент starts with 'defer', the ‘preserveAspectRatio’ атрибут on the root елемент in the referenced SVG image is also ignored (see ‘preserveAspectRatio’ for details). Instead, the ‘preserveAspectRatio’ атрибут on the referencing ‘image’ елемент defines how the SVG image content is fitted into the viewport and the ‘clip’ and ‘overflow’ властивості on the ‘image’ елемент define how the SVG image content is clipped (or not) relative to the viewport.

The value of the ‘viewBox’ атрибут to use when evaluating the ‘preserveAspectRatio’ атрибут is defined by the referenced content. For content that clearly identifies a viewBox (e.g. an SVG file with the ‘viewBox’ атрибут on the outermost svg елемент) that value should be used. For most raster content (PNG, JPEG) the bounds of the image should be used (i.e. the ‘image’ елемент has an implicit ‘viewBox’ of '0 0 raster-image-width raster-image-height'). Where no value is readily available (e.g. an SVG file with no ‘viewBox’ атрибут on the outermost svg елемент) the ‘preserveAspectRatio’ атрибут is ignored, and only the translation due to the ‘x’ & ‘y’ атрибути of the viewport is used to display the content.

For example, if the image елемент referenced a PNG or JPEG and preserveAspectRatio="xMinYMin meet", then the aspect ratio of the raster would be preserved (which means that the scale factor from image's coordinates to current user space coordinates would be the same for both X and Y), the raster would be sized as large as possible while ensuring that the entire raster fits within the viewport, and the top/left of the raster would be aligned with the top/left of the viewport as defined by the атрибути ‘x’, ‘y’, ‘width’ and ‘height’ on the ‘image’ елемент. If the value of ‘preserveAspectRatio’ was 'none' then aspect ratio of the image would not be preserved. The image would be fitted such that the top/left corner of the raster exactly aligns with coordinate (‘x’, ‘y’) and the bottom/right corner of the raster exactly aligns with coordinate (‘x’+‘width’, ‘y’+‘height’).

The resource referenced by the ‘image’ елемент represents a separate document which generates its own parse tree and document object модель (if the resource is XML). Thus, there is no inheritance of властивості into the image.

Unlike ‘use’, the ‘image’ елемент cannot reference елементи within an SVG file.

Attribute definitions:

x = "<coordinate>"

The x-axis coordinate of one corner of the rectangular region into which the referenced document is placed.
If the атрибут is not specified, the effect is as if a value of '0' were specified.
Animatable: yes.

y = "<coordinate>"

The y-axis coordinate of one corner of the rectangular region into which the referenced document is placed.
If the атрибут is not specified, the effect is as if a value of '0' were specified.
Animatable: yes.

width = "<length>"

The width of the rectangular region into which the referenced document is placed.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
Animatable: yes.

height = "<length>"

The height of the rectangular region into which the referenced document is placed.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
Animatable: yes.

xlink:href = "<iri>"

A IRI reference.
Animatable: yes.

preserveAspectRatio = "[defer] <align> [<meetOrSlice>]"

If атрибут ‘preserveAspectRatio’ is not specified, then the effect is as if a value of xMidYMid meet were specified.

Animatable: yes.

An example:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="4in" height="3in" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <desc>This graphic links to an external image
  </desc>
  <image x="200" y="200" width="100px" height="100px"
         xlink:href="myimage.png">
    <title>My image</title>
  </image>
</svg>

5.8 Умновне виконання

5.8.1 Умновне виконання overview

SVG contains a ‘switch’ елемент along with атрибути ‘requiredFeatures’, ‘requiredExtensions’ and ‘systemLanguage’ to provide an ability to specify alternate viewing depending on the capabilities of a given user agent or the user's language.

Attributes ‘requiredFeatures’, ‘requiredExtensions’ and ‘systemLanguage’ act as tests and return either true or false results. The ‘switch’ renders the first of its children for which all of these атрибути test true. If the given атрибут is not specified, then a true value is assumed.

Similar to the ‘display’ властивість, conditional processing атрибути only affect the direct rendering of елементи and do not prevent елементи from being successfully referenced by other елементи (such as via a ‘use’).

In consequence:

‘requiredFeatures’, ‘requiredExtensions’ and ‘systemLanguage’ атрибути affect ‘a’, ‘altGlyph’, ‘foreignObject’, ‘textPath’, ‘tref’, and ‘tspan’ елементи.
‘requiredFeatures’, ‘requiredExtensions’ and ‘systemLanguage’ атрибути will have no effect on ‘mask’, ‘clipPath’, and ‘pattern’ елементи.
‘requiredFeatures’, ‘requiredExtensions’ and ‘systemLanguage’ атрибути do not apply to the ‘defs’, and ‘cursor’ елементи because they are not part of the rendering tree.
‘requiredFeatures’, ‘requiredExtensions’ and ‘systemLanguage’ атрибути affect ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, and ‘set’ елементи. If the conditional statement on these animation елементи fails, the animation will never be triggered.

5.8.2 The ‘switch’ елемент

‘switch’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’

DOM Інтерфейсs:

SVGSwitchElement

The ‘switch’ елемент evaluates the ‘requiredFeatures’, ‘requiredExtensions’ and ‘systemLanguage’ атрибути on its direct child елементи in order, and then processes and renders the first child for which these атрибути evaluate to true. All others will be bypassed and therefore not rendered. If the child елемент is a container елемент such as a ‘g’, then the entire subtree is either processed/rendered or bypassed/not rendered.

Note that the values of властивості ‘display’ and ‘visibility’ have no effect on ‘switch’ елемент processing. In particular, setting ‘display’ to none on a child of a ‘switch’ елемент has no effect on true/false testing associated with ‘switch’ елемент processing.

For more information and an example, see Embedding foreign object types.

5.8.3 The ‘requiredFeatures’ атрибут

Definition of requiredFeatures:

requiredFeatures = list-of-features: The value is a list of feature strings, with the individual values separated by white space. Determines whether all of the named features are supported by the user agent. Only feature strings defined in the Feature String appendix are allowed. If all of the given features are supported, then the атрибут evaluates to true; otherwise, the current елемент and its children are skipped and thus will not be rendered.
Animatable: no.

If the атрибут is not present, then its implicit return value is "true". If a null string or empty string value is given to атрибут ‘requiredFeatures’, the атрибут returns "false".

‘requiredFeatures’ is often used in conjunction with the ‘switch’ елемент. If the ‘requiredFeatures’ is used in other situations, then it represents a simple switch on the given елемент whether to render the елемент or not.

5.8.4 The ‘requiredExtensions’ атрибут

The ‘requiredExtensions’ атрибут defines a list of required language extensions. Language extensions are capabilities within a user agent that go beyond the feature set defined in this specification. Each extension is identified by an IRI reference.

Definition of requiredExtensions:

requiredExtensions = list-of-extensions: The value is a list of IRI references which identify the required extensions, with the individual values separated by white space. Determines whether all of the named extensions are supported by the user agent. If all of the given extensions are supported, then the атрибут evaluates to true; otherwise, the current елемент and its children are skipped and thus will not be rendered.
Animatable: no.

If a given IRI reference contains white space within itself, that white space must be escaped.

If the атрибут is not present, then its implicit return value is "true". If a null string or empty string value is given to атрибут ‘requiredExtensions’, the атрибут returns "false".

‘requiredExtensions’ is often used in conjunction with the ‘switch’ елемент. If the ‘requiredExtensions’ is used in other situations, then it represents a simple switch on the given елемент whether to render the елемент or not.

The IRI names for the extension should include versioning information, such as "http://example.org/SVGExtensionXYZ/1.0", so that script writers can distinguish between different versions of a given extension.

5.8.5 The ‘systemLanguage’ атрибут

The атрибут value is a comma-separated list of language names as defined in BCP 47 [BCP47].

Evaluates to "true" if one of the languages indicated by user preferences exactly equals one of the languages given in the value of this parameter, or if one of the languages indicated by user preferences exactly equals a prefix of one of the languages given in the value of this parameter such that the first tag character following the prefix is "-".

Evaluates to "false" otherwise.

Note: This use of a prefix matching rule does not imply that language tags are assigned to languages in such a way that it is always true that if a user understands a language with a certain tag, then this user will also understand all languages with tags for which this tag is a prefix.

The prefix rule simply allows the use of prefix tags if this is the case.

Implementation note: When making the choice of linguistic preference available to the user, implementers should take into account the fact that users are not familiar with the details of language matching as described above, and should provide appropriate guidance. As an example, users may assume that on selecting "en-gb", they will be served any kind of English document if British English is not available. The user interface for setting user preferences should guide the user to add "en" to get the best matching behavior.

Multiple languages MAY be listed for content that is intended for multiple audiences. For example, content that is presented simultaneously in the original Maori and English versions, would call for:

<text systemLanguage="mi, en"><!-- content goes
          here --></text>

Якever, just because multiple languages are present within the object on which the ‘systemLanguage’ test атрибут is placed, this does not mean that it is intended for multiple linguistic audiences. An example would be a beginner's language primer, such as "A First Lesson in Latin," which is clearly intended to be used by an English-literate audience. In this case, the ‘systemLanguage’ test атрибут should only include "en".

Authoring note: Authors should realize that if several alternative language objects are enclosed in a ‘switch’, and none of them matches, this may lead to situations where no content is displayed. It is thus recommended to include a "catch-all" choice at the end of such a ‘switch’ which is acceptable in all cases.

For the ‘systemLanguage’ атрибут: Animatable: no.

If the атрибут is not present, then its implicit return value is "true". If a null string or empty string value is given to атрибут ‘systemLanguage’, the атрибут returns "false".

‘systemLanguage’ is often used in conjunction with the ‘switch’ елемент. If the ‘systemLanguage’ is used in other situations, then it represents a simple switch on the given елемент whether to render the елемент or not.

5.8.6 Applicability of test атрибути

The following list describes the applicability of the test атрибути to the елементи that do not directly produce rendering.

the test атрибути do not effect the ‘mask’, ‘clipPath’, ‘linearGradient’, ‘radialGradient’ and ‘pattern’ елементи. The test атрибути on a referenced елемент do not affect the rendering of the referencing елемент.
the test атрибути do not effect the ‘defs’, and ‘cursor’ елементи as they are not part of the rendering tree.
an animation елемент (‘animate’, ‘animateMotion’, ‘animateTransform’, ‘animateColor’ and ‘set’) will never be triggered if it has a test атрибут that evaluates to false.

5.9 Specifying whether external resources are required for proper rendering

Documents often reference and use the contents of other files (and other Web resources) as part of their rendering. In some cases, authors want to specify that particular resources are required for a document to be considered correct.

Attribute ‘externalResourcesRequired’ is available on all container елементи and to all елементи which potentially can reference external resources. It specifies whether referenced resources that are not part of the current document are required for proper rendering of the given container елемент or graphics елемент.

Attribute definition:

externalResourcesRequired = "false | true"

false: (The default value.) Indicates that resources external to the current document are optional. Document rendering can proceed even if external resources are unavailable to the current елемент and its descendants.
true: Indicates that resources external to the current document are required. If an external resource is not available, progressive rendering is suspended, the document's SVGLoad event is not fired and the animation timeline does not begin until that resource and all other required resources become available, have been parsed and are ready to be rendered. If a timeout event occurs on a required resource, then the document goes into an error state (see Error processing). The document remains in an error state until all required resources become available.

This атрибут applies to all types of resource references, including style sheets, color profiles (see Color profile descriptions) and fonts specified by an IRI reference using a ‘font-face’ елемент or a CSS @font-face specification. In particular, if an елемент sets externalResourcesRequired="true", then all style sheets must be available since any style sheet might affect the rendering of that елемент.

Attribute ‘externalResourcesRequired’ is not inheritable (from a sense of атрибут value inheritance), but if set on a container елемент, its value will apply to all елементи within the container.

Because setting externalResourcesRequired="true" on a container елемент will have the effect of disabling progressive display of the contents of that container, if that container includes елементи that reference external resources, tools that generate SVG content are cautioned against simply setting externalResourcesRequired="true" on the outermost svg елемент on a universal basis. Instead, it is better to specify externalResourcesRequired="true" on those particular graphics елементи or container елементи which specifically need the availability of external resources in order to render properly.

For ‘externalResourcesRequired’: Animatable: no.

5.10 Common атрибути

5.10.1 Attributes common to all елементи: ‘id’ and ‘xml:base’

The ‘id’ and ‘xml:base’ атрибути are available on all SVG елементи:

Attribute definitions:

id = "name": Standard XML атрибут for assigning a unique name to an елемент. Refer to the Extensible Markup Language (XML) 1.0 Recommendation [XML10].
Animatable: no.
xml:base = "<iri>": Specifies a base IRI other than the base IRI of the document or external entity. Refer to the XML Base specification [XML-BASE].
Animatable: no.

5.10.2 The ‘xml:lang’ and ‘xml:space’ атрибути

Elements that might contain character data content have атрибути ‘xml:lang’ and ‘xml:space’.

Attribute definitions:

xml:lang = "languageID": Standard XML атрибут to specify the language (e.g., English) used in the contents and атрибут values of particular елементи. Refer to the Extensible Markup Language (XML) 1.0 Recommendation [XML10].
Animatable: no.
xml:space = "{default | preserve}": Standard XML атрибут to specify whether white space is preserved in character data. The only possible values are 'default' and 'preserve'. Refer to the Extensible Markup Language (XML) 1.0 Recommendation [XML10] and to the discussion white space handling in SVG.
Animatable: no.

5.11 DOM interfaces

5.11.1 Інтерфейс SVGDocument

When an ‘svg’ елемент is embedded inline as a component of a document from another namespace, such as when an ‘svg’ елемент is embedded inline within an XHTML document [XHTML], then an SVGDocument object will not exist; instead, the root object in the document object hierarchy will be a Document object of a different type, such as an HTMLDocument object.

Якever, an SVGDocument object will indeed exist when the root елемент of the XML document hierarchy is an ‘svg’ елемент, such as when viewing a stand-alone SVG file (i.e., a file with MIME type "image/svg+xml"). In this case, the SVGDocument object will be the root object of the document object модель hierarchy.

In the case where an SVG document is embedded by reference, such as when an XHTML document has an ‘object’ елемент whose ‘href’ атрибут references an SVG document (i.e., a document whose MIME type is "image/svg+xml" and whose root елемент is thus an ‘svg’ елемент), there will exist two distinct DOM hierarchies. The first DOM hierarchy will be for the referencing document (e.g., an XHTML document). The second DOM hierarchy will be for the referenced SVG document. In this second DOM hierarchy, the root object of the document object модель hierarchy is an SVGDocument object.

The SVGDocument interface contains a similar list of атрибути and methods to the HTMLDocument interface described in the Document Object Model (HTML) Level 1 chapter of the [DOM1] specification.

interface SVGDocument : Document,
                        DocumentEvent {
  readonly атрибут DOMString title;
  readonly атрибут DOMString referrer;
  readonly атрибут DOMString domain;
  readonly атрибут DOMString URL;
  readonly атрибут SVGSVGElement rootElement;
};

Attributes:

title (readonly DOMString): The title of a document as specified by the ‘title’ sub-елемент of the ‘svg’ root елемент (i.e., <svg><title>Here is the title</title>...</svg>)
referrer (readonly DOMString): Returns the URI of the page that linked to this page. The value is an empty string if the user navigated to the page directly (not through a link, but, for example, via a bookmark).
domain (readonly DOMString): The domain name of the server that served the document, or a null string if the server cannot be identified by a domain name.
URL (readonly DOMString): The complete URI of the document.
rootElement (readonly SVGSVGElement): The root ‘svg’ in the document hierarchy.

5.11.2 Інтерфейс SVGSVGElement

A key interface definition is the SVGSVGElement interface, which is the interface that corresponds to the ‘svg’ елемент. This interface contains various miscellaneous commonly-used utility methods, such as matrix operations and the ability to control the time of redraw on visual rendering devices.

SVGSVGElement extends ViewCSS and DocumentCSS to provide access to the computed values of властивості and the override style sheet as described in DOM Level 2 Style [DOM2STYLE].

interface SVGSVGElement : SVGElement,
                          SVGTests,
                          SVGLangSpace,
                          SVGExternalResourcesRequired,
                          SVGStylable,
                          SVGLocatable,
                          SVGFitToViewBox,
                          SVGZoomAndPan,
                          DocumentEvent,
                          ViewCSS,
                          DocumentCSS {

  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
  readonly атрибут SVGAnimatedLength width;
  readonly атрибут SVGAnimatedLength height;
           атрибут DOMString contentScriptType setraises(DOMException);
           атрибут DOMString contentStyleType setraises(DOMException);
  readonly атрибут SVGRect viewport;
  readonly атрибут float pixelUnitToMillimeterX;
  readonly атрибут float pixelUnitToMillimeterY;
  readonly атрибут float screenPixelToMillimeterX;
  readonly атрибут float screenPixelToMillimeterY;
  readonly атрибут boolean useCurrentView;
  readonly атрибут SVGViewSpec currentView;
           атрибут float currentScale;
  readonly атрибут SVGPoint currentTranslate;

  unsigned long suspendRedraw(in unsigned long maxWaitMilliseconds);
  void unsuspendRedraw(in unsigned long suspendHandleID);
  void unsuspendRedrawAll();
  void forceRedraw();
  void pauseAnimations();
  void unpauseAnimations();
  boolean animationsPaused();
  float getCurrentTime();
  void setCurrentTime(in float seconds);
  NodeList getIntersectionList(in SVGRect rect, in SVGElement referenceElement);
  NodeList getEnclosureList(in SVGRect rect, in SVGElement referenceElement);
  boolean checkIntersection(in SVGElement елемент, in SVGRect rect);
  boolean checkEnclosure(in SVGElement елемент, in SVGRect rect);
  void deselectAll();
  SVGNumber createSVGNumber();
  SVGLength createSVGLength();
  SVGAngle createSVGAngle();
  SVGPoint createSVGPoint();
  SVGMatrix createSVGMatrix();
  SVGRect createSVGRect();
  SVGTransform createSVGTransform();
  SVGTransform createSVGTransformFromMatrix(in SVGMatrix matrix);
  Element getElementById(in DOMString елементId);
};

Attributes:

x (readonly SVGAnimatedLength)

Corresponds to атрибут ‘x’ on the given ‘svg’ елемент.

y (readonly SVGAnimatedLength)

Corresponds to атрибут ‘y’ on the given ‘svg’ елемент.

width (readonly SVGAnimatedLength)

Corresponds to атрибут ‘width’ on the given ‘svg’ елемент.

height (readonly SVGAnimatedLength)

Corresponds to атрибут ‘height’ on the given ‘svg’ елемент.

contentScriptType (DOMString)

Corresponds to атрибут ‘contentScriptType’ on the given ‘svg’ елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

contentStyleType (DOMString)

Corresponds to атрибут ‘contentStyleType’ on the given ‘svg’ елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

viewport (readonly SVGRect)

The position and size of the viewport (implicit or explicit) that corresponds to this ‘svg’ елемент. When the user agent is actually rendering the content, then the position and size values represent the actual values when rendering. The position and size values are unitless values in the coordinate system of the parent елемент. If no parent елемент exists (i.e., ‘svg’ елемент represents the root of the document tree), if this SVG document is embedded as part of another document (e.g., via the HTML ‘object’ елемент), then the position and size are unitless values in the coordinate system of the parent document. (If the parent uses CSS or XSL layout, then unitless values represent pixel units for the current CSS or XSL viewport, as described in the CSS2 specification.) If the parent елемент does not have a coordinate system, then the user agent should provide reasonable default values for this атрибут.

The SVGRect object is read only.

pixelUnitToMillimeterX (readonly float)

Size of a pixel units (as defined by CSS2) along the x-axis of the viewport, which represents a unit somewhere in the range of 70dpi to 120dpi, and, on systems that support this, might actually match the characteristics of the target medium. On systems where it is impossible to know the size of a pixel, a suitable default pixel size is provided.

pixelUnitToMillimeterY (readonly float)

Corresponding size of a pixel unit along the y-axis of the viewport.

screenPixelToMillimeterX (readonly float)

User interface (UI) events in DOM Level 2 indicate the screen positions at which the given UI event occurred. When the user agent actually knows the physical size of a "screen unit", this атрибут will express that information; otherwise, user agents will provide a suitable default value such as .28mm.

screenPixelToMillimeterY (readonly float)

Corresponding size of a screen pixel along the y-axis of the viewport.

useCurrentView (readonly boolean)

The initial view (i.e., before magnification and panning) of the current innermost SVG document fragment can be either the "standard" view (i.e., based on атрибути on the ‘svg’ елемент such as ‘viewBox’) or to a "custom" view (i.e., a hyperlink into a particular ‘view’ or other елемент - see Linking into SVG content: IRI fragments and SVG views). If the initial view is the "standard" view, then this атрибут is false. If the initial view is a "custom" view, then this атрибут is true.

currentView (readonly SVGViewSpec)

The definition of the initial view (i.e., before magnification and panning) of the current innermost SVG document fragment. The meaning depends on the situation:

If the initial view was a "standard" view, then:
- the values for viewBox, preserveAspectRatio and zoomAndPan within currentView will match the values for the corresponding DOM атрибути that are on SVGSVGElement directly
- the values for transform and viewTarget within currentView will be null
If the initial view was a link into a ‘view’ елемент, then:
- the values for viewBox, preserveAspectRatio and zoomAndPan within currentView will correspond to the corresponding атрибути for the given ‘view’ елемент
- the values for transform and viewTarget within currentView will be null
If the initial view was a link into another елемент (i.e., other than a ‘view’), then:
- the values for viewBox, preserveAspectRatio and zoomAndPan within currentView will match the values for the corresponding DOM атрибути that are on SVGSVGElement directly for the closest ancestor ‘svg’ елемент
- the values for transform within currentView will be null
- the viewTarget within currentView will represent the target of the link
If the initial view was a link into the SVG document fragment using an SVG view specification fragment identifier (i.e., #svgView(...)), then:
- the values for viewBox, preserveAspectRatio, zoomAndPan, transform and viewTarget within currentView will correspond to the values from the SVG view specification fragment identifier

The object itself and its contents are both read only.

currentScale (float)

On an outermost svg елемент, this атрибут indicates the current scale factor relative to the initial view to take into account user magnification and panning operations, as described under Magnification and panning. DOM атрибути currentScale and currentTranslate are equivalent to the 2x3 matrix [a b c d e f] = [currentScale 0 0 currentScale currentTranslate.x currentTranslate.y]. If "magnification" is enabled (i.e., zoomAndPan="magnify"), then the effect is as if an extra transformation were placed at the outermost level on the SVG document fragment (i.e., outside the outermost svg елемент).

When accessed on an ‘svg’ елемент that is not an outermost svg елемент, it is undefined what behavior this атрибут has.

currentTranslate (readonly SVGPoint)

On an outermost svg елемент, the corresponding translation factor that takes into account user "magnification".

When accessed on an ‘svg’ елемент that is not an outermost svg елемент, it is undefined what behavior this атрибут has.

Operations:

unsigned long suspendRedraw(in unsigned long maxWaitMilliseconds)

Takes a time-out value which indicates that redraw shall not occur until:

the corresponding unsuspendRedraw() call has been made,
an unsuspendRedrawAll() call has been made, or
its timer has timed out.

In environments that do not support interactivity (e.g., print media), then redraw shall not be suspended. Calls to suspendRedraw() and unsuspendRedraw() should, but need not be, made in balanced pairs.

To suspend redraw actions as a collection of SVG DOM changes occur, precede the changes to the SVG DOM with a method call similar to:

suspendHandleID = suspendRedraw(maxWaitMilliseconds);

and follow the changes with a method call similar to:

unsuspendRedraw(suspendHandleID);

Note that multiple suspendRedraw calls can be used at once and that each such method call is treated independently of the other suspendRedraw method calls.

Parameters

unsigned long maxWaitMilliseconds

The amount of time in milliseconds to hold off before redrawing the device. Values greater than 60 seconds will be truncated down to 60 seconds.

Returns

A number which acts as a unique identifier for the given suspendRedraw() call. This value must be passed as the parameter to the corresponding unsuspendRedraw() method call.

void unsuspendRedraw(in unsigned long suspendHandleID)

Cancels a specified suspendRedraw() by providing a unique suspend handle ID that was returned by a previous suspendRedraw() call.

Parameters

unsigned long suspendHandleID

A number which acts as a unique identifier for the desired suspendRedraw() call. The number supplied must be a value returned from a previous call to suspendRedraw(). If an invalid handle ID value is provided then the request to unsuspendRedraw() is silently ignored.

void unsuspendRedrawAll()

Cancels all currently active suspendRedraw() method calls. This method is most useful at the very end of a set of SVG DOM calls to ensure that all pending suspendRedraw() method calls have been cancelled.

void forceRedraw()

In rendering environments supporting interactivity, forces the user agent to immediately redraw all regions of the viewport that require updating.

void pauseAnimations()

Suspends (i.e., pauses) all currently running animations that are defined within the SVG document fragment corresponding to this ‘svg’ елемент, causing the animation clock corresponding to this document fragment to stand still until it is unpaused.

void unpauseAnimations()

Unsuspends (i.e., unpauses) currently running animations that are defined within the SVG document fragment, causing the animation clock to continue from the time at which it was suspended.

boolean animationsPaused()

Returns true if this SVG document fragment is in a paused state.

Returns: Boolean indicating whether this SVG document fragment is in a paused state.

float getCurrentTime()

Returns the current time in seconds relative to the start time for the current SVG document fragment. If getCurrentTime is called before the document timeline has begun (for example, by script running in a ‘script’ елемент before the document's SVGLoad event is dispatched), then 0 is returned.

Returns: The current time in seconds, or 0 if the document timeline has not yet begun.

void setCurrentTime(in float seconds)

Adjusts the clock for this SVG document fragment, establishing a new current time. If setCurrentTime is called before the document timeline has begun (for example, by script running in a ‘script’ елемент before the document's SVGLoad event is dispatched), then the value of seconds in the last invocation of the method gives the time that the document will seek to once the document timeline has begun.

Parameters

float seconds

The new current time in seconds relative to the start time for the current SVG document fragment.

NodeList getIntersectionList(in SVGRect rect, in SVGElement referenceElement)

Returns the list of graphics елементи whose rendered content intersects the supplied rectangle. Each candidate graphics елемент is to be considered a match only if the same graphics елемент can be a target of pointer events as defined in ‘pointer-events’ processing.

Parameters

SVGRect rect

The test rectangle. The values are in the initial coordinate system for the current ‘svg’ елемент.
SVGElement referenceElement

If not null, then any intersected елемент that doesn't have the referenceElement as ancestor must not be included in the returned NodeList.

Returns

A list of Elements whose content intersects the supplied rectangle. This NodeList must be implemented identically to the NodeList interface as defined in DOM Level 2 Core ([DOM2], section 1.2) with the exception that the interface is not live.

NodeList getEnclosureList(in SVGRect rect, in SVGElement referenceElement)

Returns the list of graphics елементи whose rendered content is entirely contained within the supplied rectangle. Each candidate graphics елемент is to be considered a match only if the same graphics елемент can be a target of pointer events as defined in ‘pointer-events’ processing.

Parameters

SVGRect rect

The test rectangle. The values are in the initial coordinate system for the current ‘svg’ елемент.
SVGElement referenceElement

If not null, then any intersected елемент that doesn't have the referenceElement as ancestor must not be included in the returned NodeList.

Returns

A list of Elements whose content is enclosed by the supplied rectangle. This NodeList must be implemented identically to the NodeList interface as defined in DOM Level 2 Core ([DOM2], section 1.2) with the exception that the interface is not live.

boolean checkIntersection(in SVGElement елемент, in SVGRect rect)

Returns true if the rendered content of the given елемент intersects the supplied rectangle. Each candidate graphics елемент is to be considered a match only if the same graphics елемент can be a target of pointer events as defined in ‘pointer-events’ processing.

Parameters

SVGElement елемент

The елемент on which to perform the given test.
SVGRect rect

The test rectangle. The values are in the initial coordinate system for the current ‘svg’ елемент.

Returns

True or false, depending on whether the given елемент intersects the supplied rectangle.

boolean checkEnclosure(in SVGElement елемент, in SVGRect rect)

Returns true if the rendered content of the given елемент is entirely contained within the supplied rectangle. Each candidate graphics елемент is to be considered a match only if the same graphics елемент can be a target of pointer events as defined in ‘pointer-events’ processing.

Parameters

SVGElement елемент

The елемент on which to perform the given test.
SVGRect rect

The test rectangle. The values are in the initial coordinate system for the current ‘svg’ елемент.

Returns

True or false, depending on whether the given елемент is enclosed by the supplied rectangle.

void deselectAll()

Unselects any selected objects, including any selections of text strings and type-in bars.

SVGNumber createSVGNumber()

Creates an SVGNumber object outside of any document trees. The object is initialized to a value of zero.

Returns: An SVGNumber object.

SVGLength createSVGLength()

Creates an SVGLength object outside of any document trees. The object is initialized to the value of 0 user units.

Returns: An SVGLength object.

SVGAngle createSVGAngle()

Creates an SVGAngle object outside of any document trees. The object is initialized to the value 0 degrees (unitless).

Returns: An SVGAngle object.

SVGPoint createSVGPoint()

Creates an SVGPoint object outside of any document trees. The object is initialized to the point (0,0) in the user coordinate system.

Returns: An SVGPoint object.

SVGMatrix createSVGMatrix()

Creates an SVGMatrix object outside of any document trees. The object is initialized to the identity matrix.

Returns: An SVGMatrix object.

SVGRect createSVGRect()

Creates an SVGRect object outside of any document trees. The object is initialized such that all values are set to 0 user units.

Returns: An SVGRect object.

SVGTransform createSVGTransform()

Creates an SVGTransform object outside of any document trees. The object is initialized to an identity matrix transform (SVG_TRANSFORM_MATRIX).

Returns: An SVGTransform object.

SVGTransform createSVGTransformFromMatrix(in SVGMatrix matrix)

Creates an SVGTransform object outside of any document trees. The object is initialized to the given matrix transform (i.e., SVG_TRANSFORM_MATRIX). The values from the parameter matrix are copied, the matrix parameter is not adopted as SVGTransform::matrix.

Parameters

SVGMatrix matrix

The transform matrix.

Returns

An SVGTransform object.

Element getElementById(in DOMString елементId)

Searches this SVG document fragment (i.e., the search is restricted to a subset of the document tree) for an Element whose id is given by елементId. If an Element is found, that Element is returned. If no such елемент exists, returns null. Behavior is not defined if more than one елемент has this id.

Parameters

DOMString елементId

The unique id value for an елемент.

Returns

The matching елемент.

5.11.3 Інтерфейс SVGGElement

The SVGSVGElement interface corresponds to the ‘g’ елемент.

interface SVGGElement : SVGElement,
                        SVGTests,
                        SVGLangSpace,
                        SVGExternalResourcesRequired,
                        SVGStylable,
                        SVGTransformable {
};

5.11.4 Інтерфейс SVGDefsElement

The SVGDefsElement interface corresponds to the ‘defs’ елемент.

interface SVGDefsElement : SVGElement,
                           SVGTests,
                           SVGLangSpace,
                           SVGExternalResourcesRequired,
                           SVGStylable,
                           SVGTransformable {
};

5.11.5 Інтерфейс SVGDescElement

The SVGDescElement interface corresponds to the ‘desc’ елемент.

interface SVGDescElement : SVGElement,
                           SVGLangSpace,
                           SVGStylable {
};

5.11.6 Інтерфейс SVGTitleElement

The SVGTitleElement interface corresponds to the ‘title’ елемент.

interface SVGTitleElement : SVGElement,
                            SVGLangSpace,
                            SVGStylable {
};

5.11.7 Інтерфейс SVGSymbolElement

The SVGSymbolElement interface corresponds to the ‘symbol’ елемент.

interface SVGSymbolElement : SVGElement,
                             SVGLangSpace,
                             SVGExternalResourcesRequired,
                             SVGStylable,
                             SVGFitToViewBox {
};

5.11.8 Інтерфейс SVGUseElement

The SVGUseElement interface corresponds to the ‘use’ елемент.

interface SVGUseElement : SVGElement,
                          SVGURIReference,
                          SVGTests,
                          SVGLangSpace,
                          SVGExternalResourcesRequired,
                          SVGStylable,
                          SVGTransformable {
  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
  readonly атрибут SVGAnimatedLength width;
  readonly атрибут SVGAnimatedLength height;
  readonly атрибут SVGElementInstance instanceRoot;
  readonly атрибут SVGElementInstance animatedInstanceRoot;
};

Attributes:

x (readonly SVGAnimatedLength): Corresponds to атрибут ‘x’ on the given ‘use’ елемент.
y (readonly SVGAnimatedLength): Corresponds to атрибут ‘y’ on the given ‘use’ елемент.
width (readonly SVGAnimatedLength): Corresponds to атрибут ‘width’ on the given ‘use’ елемент.
height (readonly SVGAnimatedLength): Corresponds to атрибут ‘height’ on the given ‘use’ елемент.
instanceRoot (readonly SVGElementInstance): The root of the "instance tree". See description of SVGElementInstance for a discussion on the instance tree.
animatedInstanceRoot (readonly SVGElementInstance): If the ‘xlink:href’ атрибут is being animated, contains the current animated root of the "instance tree". If the ‘xlink:href’ атрибут is not currently being animated, contains the same value as instanceRoot. See description of SVGElementInstance for a discussion on the instance tree.

5.11.9 Інтерфейс SVGElementInstance

For each ‘use’ елемент, the SVG DOM maintains a shadow tree (the "instance tree") of objects of type SVGElementInstance. An SVGElementInstance represents a single node in the instance tree. The root object in the instance tree is pointed to by the instanceRoot атрибут on the SVGUseElement object for the corresponding ‘use’ елемент.

If the ‘use’ елемент references a simple graphics елемент such as a ‘rect’, then there is only a single SVGElementInstance object, and the correspondingElement атрибут on this SVGElementInstance object is the SVGRectElement that corresponds to the referenced ‘rect’ елемент.

If the ‘use’ елемент references a ‘g’ which contains two ‘rect’ елементи, then the instance tree contains three SVGElementInstance objects, a root SVGElementInstance object whose correspondingElement is the SVGGElement object for the ‘g’, and then two child SVGElementInstance objects, each of which has its correspondingElement that is an SVGRectElement object.

If the referenced object is itself a ‘use’, or if there are ‘use’ subелементи within the referenced object, the instance tree will contain recursive expansion of the indirect references to form a complete tree. For example, if a ‘use’ елемент references a ‘g’, and the ‘g’ itself contains a ‘use’, and that ‘use’ references a ‘rect’, then the instance tree for the original (outermost) ‘use’ will consist of a hierarchy of SVGElementInstance objects, as follows:

SVGElementInstance #1 (parentNode=null, firstChild=#2, correspondingElement is the 'g')
  SVGElementInstance #2 (parentNode=#1, firstChild=#3, correspondingElement is the other 'use')
    SVGElementInstance #3 (parentNode=#2, firstChild=null, correspondingElement is the 'rect')

interface SVGElementInstance : EventTarget {
  readonly атрибут SVGElement correspondingElement;
  readonly атрибут SVGUseElement correspondingUseElement;
  readonly атрибут SVGElementInstance parentNode;
  readonly атрибут SVGElementInstanceList childNodes;
  readonly атрибут SVGElementInstance firstChild;
  readonly атрибут SVGElementInstance lastChild;
  readonly атрибут SVGElementInstance previousSibling;
  readonly атрибут SVGElementInstance nextSibling;
};

Attributes:

correspondingElement (readonly SVGElement): The corresponding елемент to which this object is an instance. For example, if a ‘use’ елемент references a ‘rect’ елемент, then an SVGElementInstance is created, with its correspondingElement being the SVGRectElement object for the ‘rect’ елемент.
correspondingUseElement (readonly SVGUseElement): The corresponding ‘use’ елемент to which this SVGElementInstance object belongs. When ‘use’ елементи are nested (e.g., a ‘use’ references another ‘use’ which references a graphics елемент such as a ‘rect’), then the correspondingUseElement is the outermost ‘use’ (i.e., the one which indirectly references the ‘rect’, not the one with the direct reference).
parentNode (readonly SVGElementInstance): The parent of this SVGElementInstance within the instance tree. All SVGElementInstance objects have a parent except the SVGElementInstance which corresponds to the елемент which was directly referenced by the ‘use’ елемент, in which case parentNode is null.
childNodes (readonly SVGElementInstanceList): An SVGElementInstanceList that contains all children of this SVGElementInstance within the instance tree. If there are no children, this is an SVGElementInstanceList containing no entries (i.e., an empty list).
firstChild (readonly SVGElementInstance): The first child of this SVGElementInstance within the instance tree. If there is no such SVGElementInstance, this returns null.
lastChild (readonly SVGElementInstance): The last child of this SVGElementInstance within the instance tree. If there is no such SVGElementInstance, this returns null.
previousSibling (readonly SVGElementInstance): The SVGElementInstance immediately preceding this SVGElementInstance. If there is no such SVGElementInstance, this returns null.
nextSibling (readonly SVGElementInstance): The SVGElementInstance immediately following this SVGElementInstance. If there is no such SVGElementInstance, this returns null.

5.11.10 Інтерфейс SVGElementInstanceList

The SVGElementInstanceList interface provides the abstraction of an ordered collection of SVGElementInstance objects, without defining or constraining how this collection is implemented.

interface SVGElementInstanceList {

  readonly атрибут unsigned long length;

  SVGElementInstance item(in unsigned long index);
};

Attributes:

length (readonly unsigned long): The number of SVGElementInstance objects in the list. The range of valid child indices is 0 to length-1 inclusive.

Operations:

SVGElementInstance item(in unsigned long index)

Returns the indexth item in the collection. If index is greater than or equal to the number of nodes in the list, this returns null.

Parameters

unsigned long index

Index into the collection.

Returns

The SVGElementInstance object at the indexth position in the SVGElementInstanceList, or null if that is not a valid index.

5.11.11 Інтерфейс SVGImageElement

The SVGImageElement interface corresponds to the ‘image’ елемент.

interface SVGImageElement : SVGElement,
                            SVGURIReference,
                            SVGTests,
                            SVGLangSpace,
                            SVGExternalResourcesRequired,
                            SVGStylable,
                            SVGTransformable {
  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
  readonly атрибут SVGAnimatedLength width;
  readonly атрибут SVGAnimatedLength height;
  readonly атрибут SVGAnimatedPreserveAspectRatio preserveAspectRatio;
};

Attributes:

x (readonly SVGAnimatedLength): Corresponds to атрибут ‘x’ on the given ‘image’ елемент.
y (readonly SVGAnimatedLength): Corresponds to атрибут ‘y’ on the given ‘image’ елемент.
width (readonly SVGAnimatedLength): Corresponds to атрибут ‘width’ on the given ‘image’ елемент.
height (readonly SVGAnimatedLength): Corresponds to атрибут ‘height’ on the given ‘image’ елемент.
preserveAspectRatio (readonly SVGAnimatedPreserveAspectRatio): Corresponds to атрибут ‘preserveAspectRatio’ on the given ‘image’ елемент.

5.11.12 Інтерфейс SVGSwitchElement

The SVGSwitchElement interface corresponds to the ‘switch’ елемент.

interface SVGSwitchElement : SVGElement,
                             SVGTests,
                             SVGLangSpace,
                             SVGExternalResourcesRequired,
                             SVGStylable,
                             SVGTransformable {
};

5.11.13 Інтерфейс GetSVGDocument

This interface provides access to an SVG document embedded by reference in another DOM-based language. The expectation is that the interface is implemented on DOM objects that allow such SVG document references, such as the DOM Element object that corresponds to an HTML ‘object’ елемент. Such DOM objects are often also required to implement the EmbeddingElement defined in the Window specification [WINDOW].

This interface is deprecated and may be dropped from future versions of the SVG specification. Authors are suggested to use the contentDocument атрибут on the EmbeddingElement interface to obtain a referenced SVG document, if that interface is available.

interface GetSVGDocument {
  SVGDocument getSVGDocument();
};

Operations:

SVGDocument getSVGDocument()

This method must return the Document object embedded content in an embedding елемент, or null if there is no document.

Note that this is equivalent to fetching the value of the EmbeddingElement::contentDocument атрибут of the embedding елемент, if the EmbeddingElement interface is also implemented. The author is advised to check that the document елемент of the returned Document is indeed an ‘svg’ елемент instead of assuming that that will always be the case.

Returns: The Document object for the referenced document, or null if there is no document.

4 Basic Data Types and Інтерфейсs

4.1 Синтаксис
4.2 Basic типи даних
4.3 Real number precision
4.4 Recognized color keyword names
4.5 Basic DOM interfaces

4.1 Синтаксис

The EBNF grammar is as used in the XML specification, with the addition of ~, a case-insensitive literal: characters in the ASCII range (only) are declared to be case-insensitive. For example, ~"Hello" will match (H|h)(e|e)(l|L)(l|L)(o|O). This makes the productions much easier to read.

?	optional, zero or one
+	one or more
*	zero or more
\|	alternation
"string"	literal
~"string"	case-insensitive literal
[]	a character range
[^]	excluded character range
()	grouping

4.2 Basic типи даних

This section defines a number of common типи даних used in the definitions of SVG властивості and атрибути. Some типи даних that are not referenced by multiple властивості and атрибути are defined inline in subsequent chapters.

Note that, as noted below, the specification of some types is different for CSS властивість values in style sheets (in the ‘style’ атрибут, ‘style’ елемент or an external style sheet) than it is for for XML атрибут values (including presentation атрибути). This is due to restrictions in the CSS grammar. For example, scientific notation is allowed in атрибути, including presentation атрибути, but not in style sheets.

<angle>

Angles are specified in one of two ways depending upon whether they are used in CSS властивість syntax or SVG presentation атрибут syntax:

When an <angle> is used in a style sheet or with a властивість in a ‘style’ атрибут, the syntax must match the following pattern:
```
angle ::= number (~"deg" | ~"grad" | ~"rad")?
```
where deg indicates degrees, grad indicates grads and rad indicates radians. The unit identifier may be in lower (recommended) or upper case.

For властивості defined in CSS2 [CSS2], an angle unit identifier must be provided (for non-zero values). For SVG-specific властивості the angle unit identifier is optional. If a unit is not provided, the angle value is assumed to be in degrees.
When an <angle> is used in an SVG presentation атрибут, the syntax must match the following pattern:
```
angle ::= number ("deg" | "grad" | "rad")?
```
The unit identifier, if present, must be in lower case; if not present, the angle value is assumed to be in degrees.

In the SVG DOM, <angle> values are represented using SVGAngle or SVGAnimatedAngle objects.

<anything>

The basic type <anything> is a sequence of zero or more characters. Specifically:

anything ::= Char*

where Char is the production for a character, as defined in XML 1.0 ([XML10], section 2.2).

<color>

The basic type <color> is a CSS2 compatible specification for a color in the sRGB color space [SRGB]. <color> applies to SVG's use of the ‘color’ властивість and is a component of the definitions of властивості ‘fill’, ‘stroke’, ‘stop-color’, ‘flood-color’ and ‘lighting-color’, which also offer optional ICC-based color specifications.

SVG supports all of the syntax alternatives for <color> defined in CSS2 syntax and basic типи даних ([CSS2], section 4.3.6), with the exception that SVG allows an expanded list of recognized color keywords names.

A <color> is either a keyword (see Recognized color keyword names) or a numerical RGB specification.

In addition to these color keywords, users may specify keywords that correspond to the colors used by objects in the user's environment. The normative definition of these keywords is found in User preferences for colors ([CSS2], section 18.2).

The format of an RGB value in hexadecimal notation is a "#" immediately followed by either three or six hexadecimal characters. The three-digit RGB notation (#rgb) is converted into six-digit form (#rrggbb) by replicating digits, not by adding zeros. For example, #fb0 expands to #ffbb00. This ensures that white (#ffffff) can be specified with the short notation (#fff) and removes any dependencies on the color depth of the display. The format of an RGB value in the functional notation is an RGB start-function followed by a comma-separated list of three numerical values (either three integer values or three percentage values) followed by ")". An RGB start-function is the case-insensitive string "rgb(", for example "RGB(" or "rGb(". For compatibility, the all-lowercase form "rgb(" is preferred. The integer value 255 corresponds to 100%, and to F or FF in the hexadecimal notation: rgb(255,255,255) = rgb(100%,100%,100%) = #FFF. White space characters are allowed around the numerical values. All RGB colors are specified in the sRGB color space [SRGB]. Using sRGB provides an unambiguous and objectively measurable definition of the color, which can be related to international standards (see [COLORIMETRY]).

color    ::= "#" hexdigit hexdigit hexdigit (hexdigit hexdigit hexdigit)?
             | "rgb(" wsp* integer comma integer comma integer wsp* ")"
             | "rgb(" wsp* integer "%" comma integer "%" comma integer "%" wsp* ")"
             | color-keyword
hexdigit ::= [0-9A-Fa-f]
comma    ::= wsp* "," wsp*

where color-keyword matches (case insensitively) one of the color keywords listed in Recognized color keyword names below, or one of the system color keywords listed in User preferences for colors ([CSS2], section 18.2).

The corresponding SVG DOM interface definitions for <color> are defined in Document Object Model CSS; in particular, see RGBColor ([DOM2STYLE], section 2.2). SVG's extension to color, including the ability to specify ICC-based colors, are represented using DOM interface SVGColor.

<coordinate>

A <coordinate> is a length in the user coordinate system that is the given distance from the origin of the user coordinate system along the relevant axis (the x-axis for X coordinates, the y-axis for Y coordinates). Its syntax is the same as that for <length>.

coordinate ::= length

Within the SVG DOM, a <coordinate> is represented as an SVGLength or an SVGAnimatedLength.

<frequency>

Frequency values are used with aural властивості. As defined in CSS2, a frequency value is a <number> immediately followed by a frequency unit identifier. The frequency unit identifiers are:

Hz: Hertz
kHz: kilo Hertz

Frequency values may not be negative.

In the SVG DOM, <frequency> values are represented using the CSSPrimitiveValue interface defined in Document Object Model CSS ([DOM2STYLE], section 2.2).

<FuncIRI>

Functional notation for an IRI: "url(" <IRI> ")".

<icccolor>

An <icccolor> is an ICC color specification. In SVG 1.1, an ICC color specification is given by a name, which references a ‘color-profile’ елемент, and one or more color component values. The grammar is as follows:

icccolor ::= "icc-color(" name (comma-wsp number)+ ")"
name     ::= [^,()#x20#x9#xD#xA] /* any char except ",", "(", ")" or wsp */

The corresponding SVG DOM interface for <icccolor> is SVGICCColor.

<integer>

An <integer> is specified as an optional sign character ("+" or "-") followed by one or more digits "0" to "9":

integer ::= [+-]? [0-9]+

If the sign character is not present, the number is non-negative.

Unless stated otherwise for a particular атрибут or властивість, the range for an <integer> encompasses (at a minimum) -2147483648 to 2147483647.

Within the SVG DOM, an <integer> is represented as a long or an SVGAnimatedInteger.

<IRI>

An Internationalized Resource Identifier (see IRI). For the specification of IRI references in SVG, see IRI references.

<length>

A length is a distance measurement, given as a number along with a unit which may be optional. Lengths are specified in one of two ways depending upon whether they are used in CSS властивість syntax or SVG presentation атрибут syntax:

When a <length> is used in a style sheet or with a властивість in a ‘style’ атрибут, the syntax must match the following pattern:
```
length ::= number (~"em" | ~"ex" | ~"px" | ~"in" | ~"cm" | ~"mm" | ~"pt" | ~"pc")?
```
See the CSS2 specification for the meanings of the unit identifiers. The unit identifier may be in lower (recommended) or upper case.

For властивості defined in CSS2 [CSS2], a length unit identifier must be provided (for non-zero values). For SVG-specific властивості, the length unit identifier is optional. If a unit is not provided, the length value represents a distance in the current user coordinate system.
When a <length> is used in an SVG presentation атрибут, the syntax must match the following pattern:
```
length ::= number ("em" | "ex" | "px" | "in" | "cm" | "mm" | "pt" | "pc" | "%")?
```
The unit identifier, if present, must be in lower case; if not present, the length value represents a distance in the current user coordinate system.

Note that the non-властивість <length> definition also allows a percentage unit identifier. The meaning of a percentage length value depends on the атрибут for which the percentage length value has been specified. Two common cases are: (a) when a percentage length value represents a percentage of the viewport width or height (refer to the section that discusses units in general), and (b) when a percentage length value represents a percentage of the bounding box width or height on a given object (refer to the section that describes object bounding box units).

In the SVG DOM, <length> values are represented using SVGLength or SVGAnimatedLength objects.

<list-of-family-names>

A <list-of-family-names> is a list of font family names using the same syntax as the ‘font-family’ властивість, excluding the <generic-family> and 'inherit' values.

<list-of-strings>

A <list-of-strings> consists of a separated sequence of <string>s. String lists are white space-separated, where white space is defined as one or more of the following consecutive characters: "space" (U+0020), "tab" (U+0009), "line feed" (U+000A) and "carriage return" (U+000D).

The following is an EBNF grammar describing the <list-of-strings> syntax:

list-of-strings ::= string
                    | string wsp list-of-strings
string          ::= [^#x9#xA#xD#x20]*
wsp             ::= [#x9#xA#xD#x20]+

<list-of-Ts>

(Where T is a type other than <string> and <family-name>.) A list consists of a separated sequence of values. Unless explicitly described differently, lists within SVG's XML атрибути can be either comma-separated, with optional white space before or after the comma, or white space-separated.

White space in lists is defined as one or more of the following consecutive characters: "space" (U+0020), "tab" (U+0009), "line feed" (U+000A), "carriage return" (U+000D) and "form-feed" (U+000C).

The following is a template for an EBNF grammar describing the <list-of-Ts> syntax:

list-of-Ts ::= T
               | T comma-wsp list-of-Ts
comma-wsp  ::= (wsp+ ","? wsp*) | ("," wsp*)
wsp        ::= (#x20 | #x9 | #xD | #xA)

Within the SVG DOM, values of a <list-of-Ts> type are represented by an interface specific for the particular type T. For example, a <list-of-lengths> is represented in the SVG DOM using an SVGLengthList or SVGAnimatedLengthList object.

<name>

A name, which is a string where a few characters of syntactic significance are disallowed.

name  ::= [^,()#x20#x9#xD#xA] /* any char except ",", "(", ")" or wsp */

<number>

Real numbers are specified in one of two ways. When used in a style sheet, a <number> is defined as follows:

number ::= integer
           | [+-]? [0-9]* "." [0-9]+

This syntax is the same as the definition in CSS ([CSS2], section 4.3.1).

When used in an SVG атрибут, a <number> is defined differently, to allow numbers with large magnitudes to be specified more concisely:

number ::= integer ([Ee] integer)?
           | [+-]? [0-9]* "." [0-9]+ ([Ee] integer)?

Within the SVG DOM, a <number> is represented as a float, SVGNumber or a SVGAnimatedNumber.

<number-optional-number>

A pair of <number>s, where the second <number> is optional.

number-optional-number ::= number
                           | number comma-wsp number

In the SVG DOM, a <number-optional-number> is represented using a pair of SVGAnimatedInteger or SVGAnimatedNumber objects.

<paint>

The values for властивості ‘fill’ and ‘stroke’ are specifications of the type of paint to use when filling or stroking a given graphics елемент. The available options and syntax for <paint> are described in Specifying paint.

Within the SVG DOM, <paint> values are represented using SVGPaint objects.

<percentage>

Percentages are specified as a number followed by a "%" character:

percentage ::= number "%"

Note that the definition of <number> depends on whether the percentage is specified in a style sheet or in an атрибут that is not also a presentation атрибут.

Percentage values are always relative to another value, for example a length. Each атрибут or властивість that allows percentages also defines the reference distance measurement to which the percentage refers.

Within the SVG DOM, a <percentage> is represented using an SVGNumber or SVGAnimatedNumber object.

<time>

A time value is a <number> immediately followed by a time unit identifier. The time unit identifiers are:

ms: milliseconds
s: seconds

In the SVG DOM, <time> values are represented using the CSSPrimitiveValue interface defined in Document Object Model CSS ([DOM2STYLE], section 2.2).

<transform-list>

A <transform-list> is used to specify a list of coordinate system transformations. A detailed description of the possible values for a <transform-list> is given in Modifying the User Coordinate System: the transform атрибут.

Within the SVG DOM, a <transform-list> value is represented using an SVGTransformList or SVGAnimatedTransformList object.

<XML-Name>

An XML name, as defined by the Name production in Extensible Markup Language (XML) 1.0 ([XML10], section 2.3).

4.3 Real number precision

Unless stated otherwise for a particular атрибут or властивість, a <number> has the capacity for at least a single-precision floating point number and has a range (at a minimum) of -3.4e+38F to +3.4e+38F.

It is recommended that higher precision floating point storage and computation be performed on operations such as coordinate system transformations to provide the best possible precision and to prevent round-off errors.

Conforming High-Quality SVG Viewers are required to use at least double-precision floating point for intermediate calculations on certain numerical operations.

4.4 Recognized color keyword names

The following is the list of recognized color keywords that can be used as a keyword value for data type <color>:

	aliceblue	rgb(240, 248, 255)
	antiquewhite	rgb(250, 235, 215)
	aqua	rgb( 0, 255, 255)
	aquamarine	rgb(127, 255, 212)
	azure	rgb(240, 255, 255)
	beige	rgb(245, 245, 220)
	bisque	rgb(255, 228, 196)
	black	rgb( 0, 0, 0)
	blanchedalmond	rgb(255, 235, 205)
	blue	rgb( 0, 0, 255)
	blueviolet	rgb(138, 43, 226)
	brown	rgb(165, 42, 42)
	burlywood	rgb(222, 184, 135)
	cadetblue	rgb( 95, 158, 160)
	chartreuse	rgb(127, 255, 0)
	chocolate	rgb(210, 105, 30)
	coral	rgb(255, 127, 80)
	cornflowerblue	rgb(100, 149, 237)
	cornsilk	rgb(255, 248, 220)
	crimson	rgb(220, 20, 60)
	cyan	rgb( 0, 255, 255)
	darkblue	rgb( 0, 0, 139)
	darkcyan	rgb( 0, 139, 139)
	darkgoldenrod	rgb(184, 134, 11)
	darkgray	rgb(169, 169, 169)
	darkgreen	rgb( 0, 100, 0)
	darkgrey	rgb(169, 169, 169)
	darkkhaki	rgb(189, 183, 107)
	darkmagenta	rgb(139, 0, 139)
	darkolivegreen	rgb( 85, 107, 47)
	darkorange	rgb(255, 140, 0)
	darkorchid	rgb(153, 50, 204)
	darkred	rgb(139, 0, 0)
	darksalmon	rgb(233, 150, 122)
	darkseagreen	rgb(143, 188, 143)
	darkslateblue	rgb( 72, 61, 139)
	darkslategray	rgb( 47, 79, 79)
	darkslategrey	rgb( 47, 79, 79)
	darkturquoise	rgb( 0, 206, 209)
	darkviolet	rgb(148, 0, 211)
	deeppink	rgb(255, 20, 147)
	deepskyblue	rgb( 0, 191, 255)
	dimgray	rgb(105, 105, 105)
	dimgrey	rgb(105, 105, 105)
	dodgerblue	rgb( 30, 144, 255)
	firebrick	rgb(178, 34, 34)
	floralwhite	rgb(255, 250, 240)
	forestgreen	rgb( 34, 139, 34)
	fuchsia	rgb(255, 0, 255)
	gainsboro	rgb(220, 220, 220)
	ghostwhite	rgb(248, 248, 255)
	gold	rgb(255, 215, 0)
	goldenrod	rgb(218, 165, 32)
	gray	rgb(128, 128, 128)
	grey	rgb(128, 128, 128)
	green	rgb( 0, 128, 0)
	greenyellow	rgb(173, 255, 47)
	honeydew	rgb(240, 255, 240)
	hotpink	rgb(255, 105, 180)
	indianred	rgb(205, 92, 92)
	indigo	rgb( 75, 0, 130)
	ivory	rgb(255, 255, 240)
	khaki	rgb(240, 230, 140)
	lavender	rgb(230, 230, 250)
	lavenderblush	rgb(255, 240, 245)
	lawngreen	rgb(124, 252, 0)
	lemonchiffon	rgb(255, 250, 205)
	lightblue	rgb(173, 216, 230)
	lightcoral	rgb(240, 128, 128)
	lightcyan	rgb(224, 255, 255)
	lightgoldenrodyellow	rgb(250, 250, 210)
	lightgray	rgb(211, 211, 211)
	lightgreen	rgb(144, 238, 144)
	lightgrey	rgb(211, 211, 211)

	lightpink	rgb(255, 182, 193)
	lightsalmon	rgb(255, 160, 122)
	lightseagreen	rgb( 32, 178, 170)
	lightskyblue	rgb(135, 206, 250)
	lightslategray	rgb(119, 136, 153)
	lightslategrey	rgb(119, 136, 153)
	lightsteelblue	rgb(176, 196, 222)
	lightyellow	rgb(255, 255, 224)
	lime	rgb( 0, 255, 0)
	limegreen	rgb( 50, 205, 50)
	linen	rgb(250, 240, 230)
	magenta	rgb(255, 0, 255)
	maroon	rgb(128, 0, 0)
	mediumaquamarine	rgb(102, 205, 170)
	mediumblue	rgb( 0, 0, 205)
	mediumorchid	rgb(186, 85, 211)
	mediumpurple	rgb(147, 112, 219)
	mediumseagreen	rgb( 60, 179, 113)
	mediumslateblue	rgb(123, 104, 238)
	mediumspringgreen	rgb( 0, 250, 154)
	mediumturquoise	rgb( 72, 209, 204)
	mediumvioletred	rgb(199, 21, 133)
	midnightblue	rgb( 25, 25, 112)
	mintcream	rgb(245, 255, 250)
	mistyrose	rgb(255, 228, 225)
	moccasin	rgb(255, 228, 181)
	navajowhite	rgb(255, 222, 173)
	navy	rgb( 0, 0, 128)
	oldlace	rgb(253, 245, 230)
	olive	rgb(128, 128, 0)
	olivedrab	rgb(107, 142, 35)
	orange	rgb(255, 165, 0)
	orangered	rgb(255, 69, 0)
	orchid	rgb(218, 112, 214)
	palegoldenrod	rgb(238, 232, 170)
	palegreen	rgb(152, 251, 152)
	paleturquoise	rgb(175, 238, 238)
	palevioletred	rgb(219, 112, 147)
	papayawhip	rgb(255, 239, 213)
	peachpuff	rgb(255, 218, 185)
	peru	rgb(205, 133, 63)
	pink	rgb(255, 192, 203)
	plum	rgb(221, 160, 221)
	powderblue	rgb(176, 224, 230)
	purple	rgb(128, 0, 128)
	red	rgb(255, 0, 0)
	rosybrown	rgb(188, 143, 143)
	royalblue	rgb( 65, 105, 225)
	saddlebrown	rgb(139, 69, 19)
	salmon	rgb(250, 128, 114)
	sandybrown	rgb(244, 164, 96)
	seagreen	rgb( 46, 139, 87)
	seashell	rgb(255, 245, 238)
	sienna	rgb(160, 82, 45)
	silver	rgb(192, 192, 192)
	skyblue	rgb(135, 206, 235)
	slateblue	rgb(106, 90, 205)
	slategray	rgb(112, 128, 144)
	slategrey	rgb(112, 128, 144)
	snow	rgb(255, 250, 250)
	springgreen	rgb( 0, 255, 127)
	steelblue	rgb( 70, 130, 180)
	tan	rgb(210, 180, 140)
	teal	rgb( 0, 128, 128)
	thistle	rgb(216, 191, 216)
	tomato	rgb(255, 99, 71)
	turquoise	rgb( 64, 224, 208)
	violet	rgb(238, 130, 238)
	wheat	rgb(245, 222, 179)
	white	rgb(255, 255, 255)
	whitesmoke	rgb(245, 245, 245)
	yellow	rgb(255, 255, 0)
	yellowgreen	rgb(154, 205, 50)

4.5 Basic DOM interfaces

4.5.1 Інтерфейс SVGElement

All of the SVG DOM interfaces that correspond directly to елементи in the SVG language (such as the SVGPathElement interface for the ‘path’ елемент) derive from the SVGElement interface.

interface SVGElement : Element {
           атрибут DOMString id setraises(DOMException);
           атрибут DOMString xmlbase setraises(DOMException);
  readonly атрибут SVGSVGElement ownerSVGElement;
  readonly атрибут SVGElement viewportElement;
};

Attributes:

id (DOMString)

The value of the ‘id’ атрибут on the given елемент, or the empty string if ‘id’ is not present.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

xmlbase (DOMString)

Corresponds to атрибут ‘xml:base’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

ownerSVGElement (readonly SVGSVGElement)

The nearest ancestor ‘svg’ елемент. Null if the given елемент is the outermost svg елемент.

viewportElement (readonly SVGElement)

The елемент which established the current viewport. Often, the nearest ancestor ‘svg’ елемент. Null if the given елемент is the outermost svg елемент.

4.5.2 Інтерфейс SVGAnimatedBoolean

Used for атрибути of type boolean which can be animated.

interface SVGAnimatedBoolean {
           атрибут boolean baseVal setraises(DOMException);
  readonly атрибут boolean animVal;
};

Attributes:

baseVal (boolean)

The base value of the given атрибут before applying any animations.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

animVal (readonly boolean)

If the given атрибут or властивість is being animated, contains the current animated value of the атрибут or властивість. If the given атрибут or властивість is not currently being animated, contains the same value as baseVal.

4.5.3 Інтерфейс SVGAnimatedString

Used for атрибути of type DOMString which can be animated.

interface SVGAnimatedString {
           атрибут DOMString baseVal setraises(DOMException);
  readonly атрибут DOMString animVal;
};

Attributes:

baseVal (DOMString)

The base value of the given атрибут before applying any animations.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

animVal (readonly DOMString)

4.5.4 Інтерфейс SVGStringList

This interface defines a list of DOMString values.

SVGStringList has the same атрибути and methods as other SVGxxxList interfaces. Implementers may consider using a single base class to implement the various SVGxxxList interfaces.

interface SVGStringList {

  readonly атрибут unsigned long numberOfItems;

  void clear() raises(DOMException);
  DOMString initialize(in DOMString newItem) raises(DOMException);
  DOMString getItem(in unsigned long index) raises(DOMException);
  DOMString insertItemBefore(in DOMString newItem, in unsigned long index) raises(DOMException);
  DOMString replaceItem(in DOMString newItem, in unsigned long index) raises(DOMException);
  DOMString removeItem(in unsigned long index) raises(DOMException);
  DOMString appendItem(in DOMString newItem) raises(DOMException);
};

Attributes:

numberOfItems (readonly unsigned long): The number of items in the list.

Operations:

void clear()

Clears all existing current items from the list, with the result being an empty list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

DOMString initialize(in DOMString newItem)

Clears all existing current items from the list and re-initializes the list to hold the single item specified by the parameter.

Parameters

DOMString newItem

The item which should become the only member of the list.

Returns

The item being inserted into the list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

DOMString getItem(in unsigned long index)

Returns the specified item from the list.

Parameters

unsigned long index

The index of the item from the list which is to be returned. The first item is number 0.

Returns

The selected item.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

DOMString insertItemBefore(in DOMString newItem, in unsigned long index)

Inserts a new item into the list at the specified position. The first item is number 0.

Parameters

DOMString newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item before which the new item is to be inserted. The first item is number 0. If the index is equal to 0, then the new item is inserted at the front of the list. If the index is greater than or equal to numberOfItems, then the new item is appended to the end of the list.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

DOMString replaceItem(in DOMString newItem, in unsigned long index)

Replaces an existing item in the list with a new item.

Parameters

DOMString newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item which is to be replaced. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

DOMString removeItem(in unsigned long index)

Removes an existing item from the list.

Parameters

unsigned long index

The index of the item which is to be removed. The first item is number 0.

Returns

The removed item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

DOMString appendItem(in DOMString newItem)

Inserts a new item at the end of the list.

Parameters

DOMString newItem

The item which is to be inserted. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

4.5.5 Інтерфейс SVGAnimatedEnumeration

Used for атрибути whose value must be a constant from a particular enumeration and which can be animated.

interface SVGAnimatedEnumeration {
           атрибут unsigned short baseVal setraises(DOMException);
  readonly атрибут unsigned short animVal;
};

Attributes:

baseVal (unsigned short)

The base value of the given атрибут before applying any animations.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

animVal (readonly unsigned short)

4.5.6 Інтерфейс SVGAnimatedInteger

Used for атрибути of basic type <integer> which can be animated.

interface SVGAnimatedInteger {
           атрибут long baseVal setraises(DOMException);
  readonly атрибут long animVal;
};

Attributes:

baseVal (long)

The base value of the given атрибут before applying any animations.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

animVal (readonly long)

4.5.7 Інтерфейс SVGNumber

Used for атрибути of basic type <number>.

interface SVGNumber {
  атрибут float value setraises(DOMException);
};

Attributes:

value (float)

The value of the given атрибут.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

4.5.8 Інтерфейс SVGAnimatedNumber

Used for атрибути of basic type <number> which can be animated.

interface SVGAnimatedNumber {
           атрибут float baseVal setraises(DOMException);
  readonly атрибут float animVal;
};

Attributes:

baseVal (float)

The base value of the given атрибут before applying any animations.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

animVal (readonly float)

4.5.9 Інтерфейс SVGNumberList

This interface defines a list of SVGNumber objects.

SVGNumberList has the same атрибути and methods as other SVGxxxList interfaces. Implementers may consider using a single base class to implement the various SVGxxxList interfaces.

An SVGNumberList object can be designated as read only, which means that attempts to modify the object will result in an exception being thrown, as described below.

interface SVGNumberList {

  readonly атрибут unsigned long numberOfItems;

  void clear() raises(DOMException);
  SVGNumber initialize(in SVGNumber newItem) raises(DOMException);
  SVGNumber getItem(in unsigned long index) raises(DOMException);
  SVGNumber insertItemBefore(in SVGNumber newItem, in unsigned long index) raises(DOMException);
  SVGNumber replaceItem(in SVGNumber newItem, in unsigned long index) raises(DOMException);
  SVGNumber removeItem(in unsigned long index) raises(DOMException);
  SVGNumber appendItem(in SVGNumber newItem) raises(DOMException);
};

Attributes:

numberOfItems (readonly unsigned long): The number of items in the list.

Operations:

void clear()

Clears all existing current items from the list, with the result being an empty list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGNumber initialize(in SVGNumber newItem)

Clears all existing current items from the list and re-initializes the list to hold the single item specified by the parameter. If the inserted item is already in a list, it is removed from its previous list before it is inserted into this list. The inserted item is the item itself and not a copy.

Parameters

SVGNumber newItem

The item which should become the only member of the list.

Returns

The item being inserted into the list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGNumber getItem(in unsigned long index)

Returns the specified item from the list. The returned item is the item itself and not a copy. Any changes made to the item are immediately reflected in the list.

Parameters

unsigned long index

The index of the item from the list which is to be returned. The first item is number 0.

Returns

The selected item.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGNumber insertItemBefore(in SVGNumber newItem, in unsigned long index)

Inserts a new item into the list at the specified position. The first item is number 0. If newItem is already in a list, it is removed from its previous list before it is inserted into this list. The inserted item is the item itself and not a copy. If the item is already in this list, note that the index of the item to insert before is before the removal of the item.

Parameters

SVGNumber newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item before which the new item is to be inserted. The first item is number 0. If the index is equal to 0, then the new item is inserted at the front of the list. If the index is greater than or equal to numberOfItems, then the new item is appended to the end of the list.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGNumber replaceItem(in SVGNumber newItem, in unsigned long index)

Replaces an existing item in the list with a new item. If newItem is already in a list, it is removed from its previous list before it is inserted into this list. The inserted item is the item itself and not a copy. If the item is already in this list, note that the index of the item to replace is before the removal of the item.

Parameters

SVGNumber newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item which is to be replaced. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGNumber removeItem(in unsigned long index)

Removes an existing item from the list.

Parameters

unsigned long index

The index of the item which is to be removed. The first item is number 0.

Returns

The removed item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGNumber appendItem(in SVGNumber newItem)

Inserts a new item at the end of the list. If newItem is already in a list, it is removed from its previous list before it is inserted into this list. The inserted item is the item itself and not a copy.

Parameters

SVGNumber newItem

The item which is to be inserted. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

4.5.10 Інтерфейс SVGAnimatedNumberList

Used for атрибути which take a list of numbers and which can be animated.

interface SVGAnimatedNumberList {
  readonly атрибут SVGNumberList baseVal;
  readonly атрибут SVGNumberList animVal;
};

Attributes:

baseVal (readonly SVGNumberList): The base value of the given атрибут before applying any animations.
animVal (readonly SVGNumberList): A read only SVGNumberList representing the current animated value of the given атрибут. If the given атрибут is not currently being animated, then the SVGNumberList will have the same contents as baseVal. The object referenced by animVal will always be distinct from the one referenced by baseVal, even when the атрибут is not animated.

4.5.11 Інтерфейс SVGLength

The SVGLength interface corresponds to the <length> basic data type.

An SVGLength object can be designated as read only, which means that attempts to modify the object will result in an exception being thrown, as described below.

interface SVGLength {

  // Length Unit Types
  const unsigned short SVG_LENGTHTYPE_UNKNOWN = 0;
  const unsigned short SVG_LENGTHTYPE_NUMBER = 1;
  const unsigned short SVG_LENGTHTYPE_PERCENTAGE = 2;
  const unsigned short SVG_LENGTHTYPE_EMS = 3;
  const unsigned short SVG_LENGTHTYPE_EXS = 4;
  const unsigned short SVG_LENGTHTYPE_PX = 5;
  const unsigned short SVG_LENGTHTYPE_CM = 6;
  const unsigned short SVG_LENGTHTYPE_MM = 7;
  const unsigned short SVG_LENGTHTYPE_IN = 8;
  const unsigned short SVG_LENGTHTYPE_PT = 9;
  const unsigned short SVG_LENGTHTYPE_PC = 10;

  readonly атрибут unsigned short unitType;
           атрибут float value setraises(DOMException);
           атрибут float valueInSpecifiedUnits setraises(DOMException);
           атрибут DOMString valueAsString setraises(DOMException);

  void newValueSpecifiedUnits(in unsigned short unitType, in float valueInSpecifiedUnits) raises(DOMException);
  void convertToSpecifiedUnits(in unsigned short unitType) raises(DOMException);
};

Constants in group “Length Unit Types”:

SVG_LENGTHTYPE_UNKNOWN (unsigned short): The unit type is not one of predefined unit types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_LENGTHTYPE_NUMBER (unsigned short): No unit type was provided (i.e., a unitless value was specified), which indicates a value in user units.
SVG_LENGTHTYPE_PERCENTAGE (unsigned short): A percentage value was specified.
SVG_LENGTHTYPE_EMS (unsigned short): A value was specified using the em units defined in CSS2.
SVG_LENGTHTYPE_EXS (unsigned short): A value was specified using the ex units defined in CSS2.
SVG_LENGTHTYPE_PX (unsigned short): A value was specified using the px units defined in CSS2.
SVG_LENGTHTYPE_CM (unsigned short): A value was specified using the cm units defined in CSS2.
SVG_LENGTHTYPE_MM (unsigned short): A value was specified using the mm units defined in CSS2.
SVG_LENGTHTYPE_IN (unsigned short): A value was specified using the in units defined in CSS2.
SVG_LENGTHTYPE_PT (unsigned short): A value was specified using the pt units defined in CSS2.
SVG_LENGTHTYPE_PC (unsigned short): A value was specified using the pc units defined in CSS2.

Attributes:

unitType (readonly unsigned short)

The type of the value as specified by one of the SVG_LENGTHTYPE_* constants defined on this interface.

value (float)

The value as a floating point value, in user units. Setting this атрибут will cause valueInSpecifiedUnits and valueAsString to be updated automatically to reflect this setting.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the length corresponds to a read only атрибут or when the object itself is read only.

valueInSpecifiedUnits (float)

The value as a floating point value, in the units expressed by unitType. Setting this атрибут will cause value and valueAsString to be updated automatically to reflect this setting.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the length corresponds to a read only атрибут or when the object itself is read only.

valueAsString (DOMString)

The value as a string value, in the units expressed by unitType. Setting this атрибут will cause value, valueInSpecifiedUnits and unitType to be updated automatically to reflect this setting.

Exceptions on setting

DOMException, code SYNTAX_ERR: Raised if the assigned string cannot be parsed as a valid <length>.
DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the length corresponds to a read only атрибут or when the object itself is read only.

Operations:

void newValueSpecifiedUnits(in unsigned short unitType, in float valueInSpecifiedUnits)

Reset the value as a number with an associated unitType, thereby replacing the values for all of the атрибути on the object.

Parameters

unsigned short unitType

The unit type for the value (e.g., SVG_LENGTHTYPE_MM).
float valueInSpecifiedUnits

The new value.

Exceptions

DOMException, code NOT_SUPPORTED_ERR: Raised if unitType is SVG_LENGTHTYPE_UNKNOWN or not a valid unit type constant (one of the other SVG_LENGTHTYPE_* constants defined on this interface).
DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the length corresponds to a read only атрибут or when the object itself is read only.

void convertToSpecifiedUnits(in unsigned short unitType)

Preserve the same underlying stored value, but reset the stored unit identifier to the given unitType. Object атрибути unitType, valueInSpecifiedUnits and valueAsString might be modified as a result of this method. For example, if the original value were "0.5cm" and the method was invoked to convert to millimeters, then the unitType would be changed to SVG_LENGTHTYPE_MM, valueInSpecifiedUnits would be changed to the numeric value 5 and valueAsString would be changed to "5mm".

Parameters

unsigned short unitType

The unit type to switch to (e.g., SVG_LENGTHTYPE_MM).

Exceptions

DOMException, code NOT_SUPPORTED_ERR: Raised if unitType is SVG_LENGTHTYPE_UNKNOWN or not a valid unit type constant (one of the other SVG_LENGTHTYPE_* constants defined on this interface).
DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the length corresponds to a read only атрибут or when the object itself is read only.

4.5.12 Інтерфейс SVGAnimatedLength

Used for атрибути of basic type <length> which can be animated.

interface SVGAnimatedLength {
  readonly атрибут SVGLength baseVal;
  readonly атрибут SVGLength animVal;
};

Attributes:

baseVal (readonly SVGLength): The base value of the given атрибут before applying any animations.
animVal (readonly SVGLength): A read only SVGLength representing the current animated value of the given атрибут. If the given атрибут is not currently being animated, then the SVGLength will have the same contents as baseVal. The object referenced by animVal will always be distinct from the one referenced by baseVal, even when the атрибут is not animated.

4.5.13 Інтерфейс SVGLengthList

This interface defines a list of SVGLength objects.

SVGLengthList has the same атрибути and methods as other SVGxxxList interfaces. Implementers may consider using a single base class to implement the various SVGxxxList interfaces.

An SVGLengthList object can be designated as read only, which means that attempts to modify the object will result in an exception being thrown, as described below.

interface SVGLengthList {

  readonly атрибут unsigned long numberOfItems;

  void clear() raises(DOMException);
  SVGLength initialize(in SVGLength newItem) raises(DOMException);
  SVGLength getItem(in unsigned long index) raises(DOMException);
  SVGLength insertItemBefore(in SVGLength newItem, in unsigned long index) raises(DOMException);
  SVGLength replaceItem(in SVGLength newItem, in unsigned long index) raises(DOMException);
  SVGLength removeItem(in unsigned long index) raises(DOMException);
  SVGLength appendItem(in SVGLength newItem) raises(DOMException);
};

Attributes:

numberOfItems (readonly unsigned long): The number of items in the list.

Operations:

void clear()

Clears all existing current items from the list, with the result being an empty list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGLength initialize(in SVGLength newItem)

Parameters

SVGLength newItem

The item which should become the only member of the list.

Returns

The item being inserted into the list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGLength getItem(in unsigned long index)

Returns the specified item from the list. The returned item is the item itself and not a copy. Any changes made to the item are immediately reflected in the list.

Parameters

unsigned long index

The index of the item from the list which is to be returned. The first item is number 0.

Returns

The selected item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGLength insertItemBefore(in SVGLength newItem, in unsigned long index)

Parameters

SVGLength newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item before which the new item is to be inserted. The first item is number 0. If the index is equal to 0, then the new item is inserted at the front of the list. If the index is greater than or equal to numberOfItems, then the new item is appended to the end of the list.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGLength replaceItem(in SVGLength newItem, in unsigned long index)

Parameters

SVGLength newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item which is to be replaced. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGLength removeItem(in unsigned long index)

Removes an existing item from the list.

Parameters

unsigned long index

The index of the item which is to be removed. The first item is number 0.

Returns

The removed item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGLength appendItem(in SVGLength newItem)

Parameters

SVGLength newItem

The item which is to be inserted. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

4.5.14 Інтерфейс SVGAnimatedLengthList

Used for атрибути of type SVGLengthList which can be animated.

interface SVGAnimatedLengthList {
  readonly атрибут SVGLengthList baseVal;
  readonly атрибут SVGLengthList animVal;
};

Attributes:

baseVal (readonly SVGLengthList): The base value of the given атрибут before applying any animations.
animVal (readonly SVGLengthList): A read only SVGLengthList representing the current animated value of the given атрибут. If the given атрибут is not currently being animated, then the SVGLengthList will have the same contents as baseVal. The object referenced by animVal will always be distinct from the one referenced by baseVal, even when the атрибут is not animated.

4.5.15 Інтерфейс SVGAngle

The SVGAngle interface corresponds to the <angle> basic data type.

An SVGAngle object can be designated as read only, which means that attempts to modify the object will result in an exception being thrown, as described below.

interface SVGAngle {

  // Angle Unit Types
  const unsigned short SVG_ANGLETYPE_UNKNOWN = 0;
  const unsigned short SVG_ANGLETYPE_UNSPECIFIED = 1;
  const unsigned short SVG_ANGLETYPE_DEG = 2;
  const unsigned short SVG_ANGLETYPE_RAD = 3;
  const unsigned short SVG_ANGLETYPE_GRAD = 4;

  readonly атрибут unsigned short unitType;
           атрибут float value setraises(DOMException);
           атрибут float valueInSpecifiedUnits setraises(DOMException);
           атрибут DOMString valueAsString setraises(DOMException);

  void newValueSpecifiedUnits(in unsigned short unitType, in float valueInSpecifiedUnits) raises(DOMException);
  void convertToSpecifiedUnits(in unsigned short unitType) raises(DOMException);
};

Constants in group “Angle Unit Types”:

SVG_ANGLETYPE_UNKNOWN (unsigned short): The unit type is not one of predefined unit types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_ANGLETYPE_UNSPECIFIED (unsigned short): No unit type was provided (i.e., a unitless value was specified). For angles, a unitless value is treated the same as if degrees were specified.
SVG_ANGLETYPE_DEG (unsigned short): The unit type was explicitly set to degrees.
SVG_ANGLETYPE_RAD (unsigned short): The unit type is radians.
SVG_ANGLETYPE_GRAD (unsigned short): The unit type is radians.

Attributes:

unitType (readonly unsigned short)

The type of the value as specified by one of the SVG_ANGLETYPE_* constants defined on this interface.

value (float)

The angle value as a floating point value, in degrees. Setting this атрибут will cause valueInSpecifiedUnits and valueAsString to be updated automatically to reflect this setting.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the angle corresponds to a read only атрибут or when the object itself is read only.

valueInSpecifiedUnits (float)

The angle value as a floating point value, in the units expressed by unitType. Setting this атрибут will cause value and valueAsString to be updated automatically to reflect this setting.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the angle corresponds to a read only атрибут or when the object itself is read only.

valueAsString (DOMString)

The angle value as a string value, in the units expressed by unitType. Setting this атрибут will cause value, valueInSpecifiedUnits and unitType to be updated automatically to reflect this setting.

Exceptions on setting

DOMException, code SYNTAX_ERR: Raised if the assigned string cannot be parsed as a valid <angle>.
DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the angle corresponds to a read only атрибут or when the object itself is read only.

Operations:

void newValueSpecifiedUnits(in unsigned short unitType, in float valueInSpecifiedUnits)

Reset the value as a number with an associated unitType, thereby replacing the values for all of the атрибути on the object.

Parameters

unsigned short unitType

The unit type for the value (e.g., SVG_ANGLETYPE_DEG).
float valueInSpecifiedUnits

The angle value.

Exceptions

DOMException, code NOT_SUPPORTED_ERR: Raised if unitType is SVG_ANGLETYPE_UNKNOWN or not a valid unit type constant (one of the other SVG_ANGLETYPE_* constants defined on this interface).
DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the angle corresponds to a read only атрибут or when the object itself is read only.

void convertToSpecifiedUnits(in unsigned short unitType)

Parameters

unsigned short unitType

The unit type to switch to (e.g., SVG_ANGLETYPE_DEG).

Exceptions

DOMException, code NOT_SUPPORTED_ERR: Raised if unitType is SVG_ANGLETYPE_UNKNOWN or not a valid unit type constant (one of the other SVG_ANGLETYPE_* constants defined on this interface).
DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the angle corresponds to a read only атрибут or when the object itself is read only.

4.5.16 Інтерфейс SVGAnimatedAngle

Used for атрибути of basic data type <angle> that can be animated.

interface SVGAnimatedAngle {
  readonly атрибут SVGAngle baseVal;
  readonly атрибут SVGAngle animVal;
};

Attributes:

baseVal (readonly SVGAngle): The base value of the given атрибут before applying any animations.
animVal (readonly SVGAngle): A read only SVGAngle representing the current animated value of the given атрибут. If the given атрибут is not currently being animated, then the SVGAngle will have the same contents as baseVal. The object referenced by animVal will always be distinct from the one referenced by baseVal, even when the атрибут is not animated.

4.5.17 Інтерфейс SVGColor

The SVGColor interface corresponds to color value definition for властивості ‘stop-color’, ‘flood-color’ and ‘lighting-color’ and is a base class for interface SVGPaint. It incorporates SVG's extended notion of color, which incorporates ICC-based color specifications.

Інтерфейс SVGColor does not correspond to the <color> basic data type. For the <color> basic data type, the applicable DOM interfaces are defined in DOM Level 2 Style; in particular, see the RGBColor interface ([DOM2STYLE], section 2.2).

Note: The SVGColor interface is deprecated, and may be dropped from future versions of the SVG specification.

interface SVGColor : CSSValue {

  // Color Types
  const unsigned short SVG_COLORTYPE_UNKNOWN = 0;
  const unsigned short SVG_COLORTYPE_RGBCOLOR = 1;
  const unsigned short SVG_COLORTYPE_RGBCOLOR_ICCCOLOR = 2;
  const unsigned short SVG_COLORTYPE_CURRENTCOLOR = 3;

  readonly атрибут unsigned short colorType;
  readonly атрибут RGBColor rgbColor;
  readonly атрибут SVGICCColor iccColor;

  void setRGBColor(in DOMString rgbColor) raises(SVGException);
  void setRGBColorICCColor(in DOMString rgbColor, in DOMString iccColor) raises(SVGException);
  void setColor(in unsigned short colorType, in DOMString rgbColor, in DOMString iccColor) raises(SVGException);
};

Constants in group “Color Types”:

SVG_COLORTYPE_UNKNOWN (unsigned short): The color type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_COLORTYPE_RGBCOLOR (unsigned short): An sRGB color has been specified without an alternative ICC color specification.
SVG_COLORTYPE_RGBCOLOR_ICCCOLOR (unsigned short): An sRGB color has been specified along with an alternative ICC color specification.
SVG_COLORTYPE_CURRENTCOLOR (unsigned short): Corresponds to when keyword currentColor has been specified.

Attributes:

colorType (readonly unsigned short): The type of the value as specified by one of the SVG_COLORTYPE_* constants defined on this interface.
rgbColor (readonly RGBColor): The color specified in the sRGB color space.
iccColor (readonly SVGICCColor): The alternate ICC color specification.

Operations:

void setRGBColor(in DOMString rgbColor)

Modifies the color value to be the specified sRGB color without an alternate ICC color specification.

Parameters

DOMString rgbColor

A string that matches <color>, which specifies the new sRGB color value.

Exceptions

SVGException, code SVG_INVALID_VALUE_ERR: Raised if rgbColor does not match <color>.

void setRGBColorICCColor(in DOMString rgbColor, in DOMString iccColor)

Modifies the color value to be the specified sRGB color with an alternate ICC color specification.

Parameters

DOMString rgbColor

A string that matches <color>, which specifies the new sRGB color value.
DOMString iccColor

A string that matches <icccolor>, which specifies the alternate ICC color specification.

Exceptions

SVGException, code SVG_INVALID_VALUE_ERR: Raised if rgbColor does not match <color> or if iccColor does not match <icccolor>.

void setColor(in unsigned short colorType, in DOMString rgbColor, in DOMString iccColor)

Sets the color value as specified by the parameters. If colorType requires an RGBColor, then rgbColor must be a string that matches <color>; otherwise, rgbColor. must be null. If colorType requires an SVGICCColor, then iccColor must be a string that matches <icccolor>; otherwise, iccColor must be null.

Parameters

unsigned short colorType

One of the defined constants for colorType.
DOMString rgbColor

The specification of an sRGB color, or null.
DOMString iccColor

The specification of an ICC color, or null.

Exceptions

SVGException, code SVG_INVALID_VALUE_ERR: Raised if one of the parameters has an invalid value.

4.5.18 Інтерфейс SVGICCColor

The SVGICCColor interface expresses an ICC-based color specification.

Note: The SVGICCColor interface is deprecated, and may be dropped from future versions of the SVG specification.

interface SVGICCColor {
           атрибут DOMString colorProfile setraises(DOMException);
  readonly атрибут SVGNumberList colors;
};

Attributes:

colorProfile (DOMString)

The name of the color profile, which is the first parameter of an ICC color specification.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

colors (readonly SVGNumberList)

The list of color values that define this ICC color. Each color value is an arbitrary floating point number.

4.5.19 Інтерфейс SVGRect

Represents rectangular geometry. Rectangles are defined as consisting of a (x,y) coordinate pair identifying a minimum X value, a minimum Y value, and a width and height, which are usually constrained to be non-negative.

An SVGRect object can be designated as read only, which means that attempts to modify the object will result in an exception being thrown, as described below.

interface SVGRect {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float width setraises(DOMException);
  атрибут float height setraises(DOMException);
};

Attributes:

x (float)

The x coordinate of the rectangle, in user units.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the rectangle corresponds to a read only атрибут or when the object itself is read only.

y (float)

The y coordinate of the rectangle, in user units.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the rectangle corresponds to a read only атрибут or when the object itself is read only.

width (float)

The width coordinate of the rectangle, in user units.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the rectangle corresponds to a read only атрибут or when the object itself is read only.

height (float)

The height coordinate of the rectangle, in user units.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the rectangle corresponds to a read only атрибут or when the object itself is read only.

4.5.20 Інтерфейс SVGAnimatedRect

Used for атрибути of type SVGRect which can be animated.

interface SVGAnimatedRect {
  readonly атрибут SVGRect baseVal;
  readonly атрибут SVGRect animVal;
};

Attributes:

baseVal (readonly SVGRect): The base value of the given атрибут before applying any animations.
animVal (readonly SVGRect): A read only SVGRect representing the current animated value of the given атрибут. If the given атрибут is not currently being animated, then the SVGRect will have the same contents as baseVal. The object referenced by animVal will always be distinct from the one referenced by baseVal, even when the атрибут is not animated.

4.5.21 Інтерфейс SVGUnitTypes

The SVGUnitTypes interface defines a commonly used set of constants and is a base interface used by SVGGradientElement, SVGPatternElement, SVGClipPathElement, SVGMaskElement and SVGFilterElement.

interface SVGUnitTypes {
  // Unit Types
  const unsigned short SVG_UNIT_TYPE_UNKNOWN = 0;
  const unsigned short SVG_UNIT_TYPE_USERSPACEONUSE = 1;
  const unsigned short SVG_UNIT_TYPE_OBJECTBOUNDINGBOX = 2;
};

Constants in group “Unit Types”:

SVG_UNIT_TYPE_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_UNIT_TYPE_USERSPACEONUSE (unsigned short): Corresponds to value 'userSpaceOnUse'.
SVG_UNIT_TYPE_OBJECTBOUNDINGBOX (unsigned short): Corresponds to value 'objectBoundingBox'.

4.5.22 Інтерфейс SVGStylable

The SVGStylable interface is implemented on all objects corresponding to SVG елементи that can have ‘style’, ‘class’ and presentation атрибути specified on them. It is thus an ancestor interface for many of the interfaces defined in this specification.

interface SVGStylable {

  readonly атрибут SVGAnimatedString className;
  readonly атрибут CSSStyleDeclaration style;

  CSSValue getPresentationAttribute(in DOMString name);
};

Attributes:

className (readonly SVGAnimatedString): Corresponds to атрибут ‘class’ on the given елемент.
style (readonly CSSStyleDeclaration): Corresponds to атрибут ‘style’ on the given елемент. If the user agent does not support styling with CSS, then this атрибут must always have the value of null.

Operations:

CSSValue getPresentationAttribute(in DOMString name)

Returns the base (i.e., static) value of a given presentation атрибут as an object of type CSSValue. The returned object is live; changes to the objects represent immediate changes to the objects to which the CSSValue is attached.

Note: The getPresentationAttribute method is deprecated, and may be dropped from future versions of the SVG specification.

Parameters

DOMString name

The name of the presentation атрибут whose value is to be returned.

Returns

The static/base value of the given presentation атрибут as a CSSValue, or null if the given атрибут does not have a specified value.

4.5.23 Інтерфейс SVGLocatable

Інтерфейс SVGLocatable is for all елементи which either have a ‘transform’ атрибут or don't have a ‘transform’ атрибут but whose content can have a bounding box in current user space.

interface SVGLocatable {

  readonly атрибут SVGElement nearestViewportElement;
  readonly атрибут SVGElement farthestViewportElement;

  SVGRect getBBox();
  SVGMatrix getCTM();
  SVGMatrix getScreenCTM();
  SVGMatrix getTransformToElement(in SVGElement елемент) raises(SVGException);
};

Attributes:

nearestViewportElement (readonly SVGElement): The елемент which established the current viewport. Often, the nearest ancestor ‘svg’ елемент. Null if the current елемент is the outermost svg елемент.
farthestViewportElement (readonly SVGElement): The farthest ancestor ‘svg’ елемент. Null if the current елемент is the outermost svg елемент.

Operations:

SVGRect getBBox()

Returns the tight bounding box in current user space (i.e., after application of the ‘transform’ атрибут, if any) on the geometry of all contained graphics елементи, exclusive of stroking, clipping, masking and filter effects). Note that getBBox must return the actual bounding box at the time the method was called, even in case the елемент has not yet been rendered.

Returns: An SVGRect object that defines the bounding box.

SVGMatrix getCTM()

Returns the transformation matrix from current user units (i.e., after application of the ‘transform’ атрибут, if any) to the viewport coordinate system for the nearestViewportElement.

Returns: An SVGMatrix object that defines the CTM.

SVGMatrix getScreenCTM()

Returns the transformation matrix from current user units (i.e., after application of the ‘transform’ атрибут, if any) to the parent user agent's notice of a "pixel". For display devices, ideally this represents a physical screen pixel. For other devices or environments where physical pixel sizes are not known, then an algorithm similar to the CSS2 definition of a "pixel" can be used instead. Note that null is returned if this елемент is not hooked into the document tree. This method would have been more aptly named as getClientCTM, but the name getScreenCTM is kept for historical reasons.

Returns: An SVGMatrix object that defines the given transformation matrix.

SVGMatrix getTransformToElement(in SVGElement елемент)

Returns the transformation matrix from the user coordinate system on the current елемент (after application of the ‘transform’ атрибут, if any) to the user coordinate system on parameter елемент (after application of its ‘transform’ атрибут, if any).

Parameters

SVGElement елемент

The target елемент.

Returns

An SVGMatrix object that defines the transformation.

Exceptions

SVGException, code SVG_MATRIX_NOT_INVERTABLE: Raised if the currently defined transformation matrices make it impossible to compute the given matrix (e.g., because one of the transformations is singular).

4.5.24 Інтерфейс SVGTransformable

Інтерфейс SVGTransformable contains властивості and methods that apply to all елементи which have атрибут ‘transform’.

interface SVGTransformable : SVGLocatable {
  readonly атрибут SVGAnimatedTransformList transform;
};

Attributes:

transform (readonly SVGAnimatedTransformList): Corresponds to атрибут ‘transform’ on the given елемент.

4.5.25 Інтерфейс SVGTests

Інтерфейс SVGTests defines an interface which applies to all елементи which have атрибути ‘requiredFeatures’, ‘requiredExtensions’ and ‘systemLanguage’.

interface SVGTests {

  readonly атрибут SVGStringList requiredFeatures;
  readonly атрибут SVGStringList requiredExtensions;
  readonly атрибут SVGStringList systemLanguage;

  boolean hasExtension(in DOMString extension);
};

Attributes:

requiredFeatures (readonly SVGStringList): Corresponds to атрибут ‘requiredFeatures’ on the given елемент.
requiredExtensions (readonly SVGStringList): Corresponds to атрибут ‘requiredExtensions’ on the given елемент.
systemLanguage (readonly SVGStringList): Corresponds to атрибут ‘systemLanguage’ on the given елемент.

Operations:

boolean hasExtension(in DOMString extension)

Returns true if the user agent supports the given extension, specified by a URI.

Parameters

DOMString extension

The name of the extension, expressed as a URI.

Returns

True or false, depending on whether the given extension is supported.

4.5.26 Інтерфейс SVGLangSpace

Інтерфейс SVGLangSpace defines an interface which applies to all елементи which have атрибути ‘xml:lang’ and ‘xml:space’.

interface SVGLangSpace {
  атрибут DOMString xmllang setraises(DOMException);
  атрибут DOMString xmlspace setraises(DOMException);
};

Attributes:

xmllang (DOMString)

Corresponds to атрибут ‘xml:lang’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

xmlspace (DOMString)

Corresponds to атрибут ‘xml:space’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

4.5.27 Інтерфейс SVGExternalResourcesRequired

Інтерфейс SVGExternalResourcesRequired defines an interface which applies to all елементи where this елемент or one of its descendants can reference an external resource.

interface SVGExternalResourcesRequired {
  readonly атрибут SVGAnimatedBoolean externalResourcesRequired;
};

Attributes:

externalResourcesRequired (readonly SVGAnimatedBoolean): Corresponds to атрибут ‘externalResourcesRequired’ on the given елемент. Note that the SVG DOM defines the атрибут ‘externalResourcesRequired’ as being of type SVGAnimatedBoolean, whereas the SVG language definition says that ‘externalResourcesRequired’ is not animated. Because the SVG language definition states that ‘externalResourcesRequired’ cannot be animated, the animVal will always be the same as the baseVal.

4.5.28 Інтерфейс SVGFitToViewBox

Інтерфейс SVGFitToViewBox defines DOM атрибути that apply to елементи which have XML атрибути ‘viewBox’ and ‘preserveAspectRatio’.

interface SVGFitToViewBox {
  readonly атрибут SVGAnimatedRect viewBox;
  readonly атрибут SVGAnimatedPreserveAspectRatio preserveAspectRatio;
};

Attributes:

viewBox (readonly SVGAnimatedRect): Corresponds to атрибут ‘viewBox’ on the given елемент.
preserveAspectRatio (readonly SVGAnimatedPreserveAspectRatio): Corresponds to атрибут ‘preserveAspectRatio’ on the given елемент.

4.5.29 Інтерфейс SVGZoomAndPan

The SVGZoomAndPan interface defines атрибут zoomAndPan and associated constants.

interface SVGZoomAndPan {

  // Zoom and Pan Types
  const unsigned short SVG_ZOOMANDPAN_UNKNOWN = 0;
  const unsigned short SVG_ZOOMANDPAN_DISABLE = 1;
  const unsigned short SVG_ZOOMANDPAN_MAGNIFY = 2;

  атрибут unsigned short zoomAndPan setraises(DOMException);
};

Constants in group “Zoom and Pan Types”:

SVG_ZOOMANDPAN_UNKNOWN (unsigned short): The enumeration was set to a value that is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_ZOOMANDPAN_DISABLE (unsigned short): Corresponds to value 'disable'.
SVG_ZOOMANDPAN_MAGNIFY (unsigned short): Corresponds to value 'magnify'.

Attributes:

zoomAndPan (unsigned short)

Corresponds to атрибут ‘zoomAndPan’ on the given елемент. The value must be one of the SVG_ZOOMANDPAN_* constants defined on this interface.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

4.5.30 Інтерфейс SVGViewSpec

The interface corresponds to an SVG View Specification.

interface SVGViewSpec : SVGZoomAndPan,
                        SVGFitToViewBox {
  readonly атрибут SVGTransformList transform;
  readonly атрибут SVGElement viewTarget;
  readonly атрибут DOMString viewBoxString;
  readonly атрибут DOMString preserveAspectRatioString;
  readonly атрибут DOMString transformString;
  readonly атрибут DOMString viewTargetString;
};

Attributes:

transform (readonly SVGTransformList): Corresponds to the transform setting on the SVG View Specification.
viewTarget (readonly SVGElement): Corresponds to the viewTarget setting on the SVG View Specification.
viewBoxString (readonly DOMString): Corresponds to the viewBox setting on the SVG View Specification.
preserveAspectRatioString (readonly DOMString): Corresponds to the preserveAspectRatio setting on the SVG View Specification.
transformString (readonly DOMString): Corresponds to the transform setting on the SVG View Specification.
viewTargetString (readonly DOMString): Corresponds to the viewTarget setting on the SVG View Specification.

4.5.31 Інтерфейс SVGURIReference

Інтерфейс SVGURIReference defines an interface which applies to all елементи which have the collection of XLink атрибути, such as ‘xlink:href’, which define a URI reference.

interface SVGURIReference {
  readonly атрибут SVGAnimatedString href;
};

Attributes:

href (readonly SVGAnimatedString): Corresponds to атрибут ‘xlink:href’ on the given елемент.

4.5.32 Інтерфейс SVGCSSRule

SVG extends interface CSSRule with interface SVGCSSRule by adding an SVGColorProfileRule rule to allow for specification of ICC-based color.

It is likely that this extension will become part of a future version of CSS and DOM.

interface SVGCSSRule : CSSRule {
  const unsigned short COLOR_PROFILE_RULE = 7;
};

Constants:

COLOR_PROFILE_RULE (unsigned short): The rule is an @color-profile.

4.5.33 Інтерфейс SVGRenderingIntent

The SVGRenderingIntent interface defines the enumerated list of possible values for ‘rendering-intent’ атрибути or descriptors.

interface SVGRenderingIntent {
  // Rendering Intent Types
  const unsigned short RENDERING_INTENT_UNKNOWN = 0;
  const unsigned short RENDERING_INTENT_AUTO = 1;
  const unsigned short RENDERING_INTENT_PERCEPTUAL = 2;
  const unsigned short RENDERING_INTENT_RELATIVE_COLORIMETRIC = 3;
  const unsigned short RENDERING_INTENT_SATURATION = 4;
  const unsigned short RENDERING_INTENT_ABSOLUTE_COLORIMETRIC = 5;
};

Constants in group “Rendering Intent Types”:

RENDERING_INTENT_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
RENDERING_INTENT_AUTO (unsigned short): Corresponds to a value of 'auto'.
RENDERING_INTENT_PERCEPTUAL (unsigned short): Corresponds to a value of 'perceptual'.
RENDERING_INTENT_RELATIVE_COLORIMETRIC (unsigned short): Corresponds to a value of 'relative-colorimetric'.
RENDERING_INTENT_SATURATION (unsigned short): Corresponds to a value of 'saturation'.
RENDERING_INTENT_ABSOLUTE_COLORIMETRIC (unsigned short): Corresponds to a value of 'absolute-colorimetric'.

6 Styling

6.1 SVG's властивості стилю
6.2 Usage scenarios for styling
6.3 Alternative ways to specify властивості стилю
6.4 Specifying властивості using the presentation атрибути
6.5 Styling with XSL
6.6 Styling with CSS
6.7 Case sensitivity of властивість names and values
6.8 Facilities from CSS and XSL used by SVG
6.9 Referencing external style sheets
6.10 The ‘style’ елемент
6.11 The ‘class’ атрибут
6.12 The ‘style’ атрибут
6.13 Specifying the default style sheet language
6.14 Property inheritance
6.15 The scope/range of styles
6.16 User agent style sheet
6.17 Aural style sheets
6.18 DOM interfaces
- 6.18.1 Інтерфейс SVGStyleElement

6.1 SVG's властивості стилю

SVG uses властивості стилю to describe many of its document parameters. Styling властивості define how the graphics елементи in the SVG content are to be rendered. SVG uses властивості стилю for the following:

Parameters which are clearly visual in nature and thus lend themselves to styling. Examples include all атрибути that define how an object is "painted," such as fill and stroke colors, linewidths and dash styles.
Parameters having to do with text styling such as font family and size.
Parameters which impact the way that graphical елементи are rendered, such as specifying clipping paths, masks, arrowheads, markers and filter effects.

SVG shares many of its властивості стилю with CSS [CSS2] and XSL [XSL]. Except for any additional SVG-specific rules explicitly mentioned in this specification, the normative definition of властивості that are shared with CSS and XSL is the definition of the властивість from the CSS2 specification [CSS2].

The following властивості are shared between CSS2 and SVG. Most of these властивості are also defined in XSL:

Font властивості:
Text властивості:
Other властивості for visual media:
- ‘clip’, only applicable to outermost svg елемент.
- ‘color’, used to provide a potential indirect value (currentColor) for the ‘fill’, ‘stroke’, ‘stop-color’, ‘flood-color’ and ‘lighting-color’ властивості. (The SVG властивості which support color allow a color specification which is extended from CSS2 to accommodate color definitions in arbitrary color spaces. See Color profile descriptions.)
- ‘cursor’
- ‘display’
- ‘overflow’, only applicable to елементи which establish a new viewport.
- ‘visibility’

The following SVG властивості are not defined in CSS2. The complete normative definitions for these властивості are found in this specification:

Clipping, Masking and Compositing властивості:
Filter Effects властивості:
Gradient властивості:
- ‘stop-color’
- ‘stop-opacity’
Interactivity властивості:
- ‘pointer-events’
Color and Painting властивості:
Text властивості:

A table that lists and summarizes the властивості стилю can be found in the Property Index.

6.2 Usage scenarios for styling

SVG has many usage scenarios, each with different needs. Here are three common usage scenarios:

SVG content used as an exchange format (style sheet language-independent):

In some usage scenarios, reliable interoperability of SVG content across software tools is the main goal. Since support for a particular style sheet language is not guaranteed across all implementations, it is a requirement that SVG content can be fully specified without the use of a style sheet language.
SVG content generated as the output from XSLT:

XSLT offers the ability to take a stream of arbitrary XML content as input, apply potentially complex transformations, and then generate SVG content as output [XSLT]. XSLT can be used to transform XML data extracted from databases into an SVG graphical representation of that data. It is a requirement that fully specified SVG content can be generated from XSLT.
SVG content styled with CSS:

CSS is a widely implemented declarative language for assigning властивості стилю to XML content, including SVG [CSS2]. It represents a combination of features, simplicity and compactness that makes it very suitable for many applications of SVG. It is a requirement that CSS styling can be applied to SVG content.

6.3 Alternative ways to specify властивості стилю

Styling властивості can be assigned to SVG елементи in the following two ways:

Presentation атрибути

Styling властивості can be assigned using SVG's presentation атрибути. For each styling властивість defined in this specification, there is a corresponding XML presentation атрибут available on all relevant SVG елементи. Detailed information on the presentation атрибути can be found in Specifying властивості using the presentation атрибути.

The presentation атрибути are style sheet language independent and thus are applicable to usage scenario 1 above (i.e., tool interoperability). Because it is straightforward to assign values to XML атрибути from XSLT, the presentation атрибути are well-suited to usage scenario 2 above (i.e., SVG generation from XSLT). (See Styling with XSL below.)

Conforming SVG Interpreters and Conforming SVG Viewers are required to support SVG's presentation атрибути.
CSS Stylesheets

To support usage scenario 3 above, SVG content can be styled with CSS. For more information, see Styling with CSS.

Conforming SVG Interpreters and Conforming SVG Viewers that support CSS styling of generic (i.e., text-based) XML content are required to also support CSS styling of SVG content.

6.4 Specifying властивості using the presentation атрибути

For each styling властивість defined in this specification (see Property Index), there is a corresponding XML атрибут (the presentation атрибут) with the same name that is available on all relevant SVG елементи. For example, SVG has a ‘fill’ властивість that defines how to paint the interior of a shape. There is a corresponding presentation атрибут with the same name (i.e., ‘fill’) that can be used to specify a value for the ‘fill’ властивість on a given елемент.

The following example shows how the ‘fill’ and ‘stroke’ властивості can be specified on a ‘rect’ using the ‘fill’ and ‘stroke’ presentation атрибути. The rectangle will be filled with red and outlined with blue:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg" version="1.1"
     width="10cm" height="5cm" viewBox="0 0 1000 500">
  <rect x="200" y="100" width="600" height="300" 
        fill="red" stroke="blue" stroke-width="3"/>
</svg>

The presentation атрибути offer the following advantages:

Broad support. All versions of Conforming SVG Interpreters and Conforming SVG Viewers are required to support the presentation атрибути.
Simplicity. Styling властивості can be attached to елементи by simply providing a value for the presentation атрибут on the proper елементи.
Restyling. SVG content that uses the presentation атрибути is highly compatible with downstream processing using XSLT [XSLT] [XSLT2] or supplemental styling by adding CSS style rules to override some of the presentation атрибути.
Convenient generation using XSLT. In some cases, XSLT can be used to generate fully styled SVG content. The presentation атрибути are compatible with convenient generation of SVG from XSLT.

In some situations, SVG content that uses the presentation атрибути has potential limitations versus SVG content that is styled with a style sheet language such as CSS (see Styling with CSS). In other situations, such as when an XSLT style sheet generates SVG content from semantically rich XML source files, the limitations below may not apply. Depending on the situation, some of the following potential limitations may or may not apply to the presentation атрибути:

Styling attached to content. The presentation атрибути are attached directly to particular елементи, thereby diminishing potential advantages that comes from abstracting styling from content, such as the ability to restyle documents for different uses and environments.
Flattened data модель. In and of themselves, the presentation атрибути do not offer the higher level abstractions that you get with a styling system, such as the ability to define named collections of властивості which are applied to particular categories of елементи. The result is that, in many cases, important higher level semantic information can be lost, potentially making document reuse and restyling more difficult.
Potential increase in file size. Many types of graphics use similar властивості стилю across multiple елементи. For example, a company organization chart might assign one collection of властивості стилю to the boxes around temporary workers (e.g., dashed outlines, red fill), and a different collection of властивості стилю to permanent workers (e.g., solid outlines, blue fill). Styling systems such as CSS allow collections of властивості to be defined once in a file. With the styling атрибути, it might be necessary to specify presentation атрибути on each different елемент.
Potential difficulty when embedded into a CSS-styled parent document. When SVG content is embedded in other XML, and the desire is to style all aspects of the compound document with CSS, use of the presentation атрибути might introduce complexity and difficulty. In this case, it is sometimes easier if the SVG content does not use the presentation атрибути and instead is styled using CSS facilities.

For user agents that support CSS, the presentation атрибути must be translated to corresponding CSS style rules according to rules described in Precedence of non-CSS presentational hints ([CSS2], section 6.4.4), with the additional clarification that the presentation атрибути are conceptually inserted into a new author style sheet which is the first in the author style sheet collection. The presentation атрибути thus will participate in the CSS2 cascade as if they were replaced by corresponding CSS style rules placed at the start of the author style sheet with a specificity of zero. In general, this means that the presentation атрибути have lower priority than other CSS style rules specified in author style sheets or ‘style’ атрибути.

User agents that do not support CSS must ignore any CSS style rules defined in CSS style sheets and ‘style’ атрибути. In this case, the CSS cascade does not apply. (Inheritance of властивості, however, does apply. See Property inheritance.)

An !important declaration ([CSS2], section 6.4.2) within a presentation атрибут definition is an invalid value.

Animation of presentation атрибути is equivalent to animating the corresponding властивість. Thus, the same effect occurs from animating the presentation атрибут with атрибутType="XML" as occurs with animating the corresponding властивість with атрибутType="CSS" (see ‘атрибутType’).

6.5 Styling with XSL

XSL style sheets [XSLT] [XSLT2] define how to transform XML content into something else, usually other XML. When XSLT is used in conjunction with SVG, sometimes SVG content will serve as both input and output for XSL style sheets. Other times, XSL style sheets will take non-SVG content as input and generate SVG content as output.

The following example uses an external XSL style sheet to transform SVG content into modified SVG content (see Referencing external style sheets). The style sheet sets the ‘fill’ and ‘stroke’ властивості on all rectangles to red and blue, respectively:

mystyle.xsl
<?xml version="1.0" standalone="no"?>
<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:svg="http://www.w3.org/2000/svg">
  <xsl:output
    method="xml"
    encoding="utf-8"
    doctype-public="-//W3C//DTD SVG 1.1//EN"
    doctype-system="http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"/>
  <!-- Add version to topmost 'svg' елемент -->
  <xsl:template match="/svg:svg">
    <xsl:copy>
      <xsl:copy-of select="@*"/>
      <xsl:атрибут name="version">1.1</xsl:атрибут>
      <xsl:apply-templates/>
    </xsl:copy>
  </xsl:template>
  <!-- Add styling to all 'rect' елементи -->
  <xsl:template match="svg:rect">
    <xsl:copy>
      <xsl:copy-of select="@*"/>
      <xsl:атрибут name="fill">red</xsl:атрибут>
      <xsl:атрибут name="stroke">blue</xsl:атрибут>
      <xsl:атрибут name="stroke-width">3</xsl:атрибут>
    </xsl:copy>
  </xsl:template>
</xsl:stylesheet>

SVG file to be transformed by mystyle.xsl
<?xml version="1.0" standalone="no"?>
<?xml-stylesheet href="mystyle.xsl" type="application/xml"?>
<svg xmlns="http://www.w3.org/2000/svg"
     width="10cm" height="5cm">
  <rect x="2cm" y="1cm" width="6cm" height="3cm"/>
</svg>

SVG content after applying mystyle.xsl
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
      "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg"
     width="10cm" height="5cm" version="1.1">
  <rect x="2cm" y="1cm" width="6cm" height="3cm" fill="red" stroke="blue" stroke-width="3"/>
</svg>

6.6 Styling with CSS

SVG implementations that support CSS are required to support the following:

External CSS style sheets referenced from the current document (see Referencing external style sheets)
Internal CSS style sheets (i.e., style sheets embedded within the current document, such as within an SVG ‘style’ елемент)
Inline style (i.e., CSS властивість declarations within a ‘style’ атрибут on a particular SVG елемент)

The following example shows the use of an external CSS style sheet to set the ‘fill’ and ‘stroke’ властивості on all rectangles to red and blue, respectively:

mystyle.css
rect {
  fill: red;
  stroke: blue;
  stroke-width: 3
}

SVG file referencing mystyle.css
<?xml version="1.0" standalone="no"?>
<?xml-stylesheet href="mystyle.css" type="text/css"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg" version="1.1"
     width="10cm" height="5cm" viewBox="0 0 1000 500">
  <rect x="200" y="100" width="600" height="300"/>
</svg>

View this example as SVG (SVG-enabled browsers only)

CSS style sheets can be embedded within SVG content inside of a ‘style’ елемент. The following example uses an internal CSS style sheet to achieve the same result as the previous example:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg" version="1.1"
     width="10cm" height="5cm" viewBox="0 0 1000 500">
  <defs>
    <style type="text/css"><![CDATA[
      rect {
        fill: red;
        stroke: blue;
        stroke-width: 3
      }
    ]]></style>
  </defs>
  <rect x="200" y="100" width="600" height="300"/>
</svg>

View this example as SVG (SVG-enabled browsers only)

Note how the CSS style sheet is placed within a CDATA construct (i.e., <![CDATA[ ... ]]>). Placing internal CSS style sheets within CDATA blocks is sometimes necessary since CSS style sheets can include characters, such as ">", which conflict with XML parsers. Even if a given style sheet does not use characters that conflict with XML parsing, it is highly recommended that internal style sheets be placed inside CDATA blocks.

Implementations that support CSS are also required to support CSS inline style. Similar to the ‘style’ атрибут in HTML, CSS inline style can be declared within a ‘style’ атрибут in SVG by specifying a semicolon-separated list of властивість declarations, where each властивість declaration has the form "name: value". Note that властивість declarations inside the ‘style’ атрибут must follow CSS style rules, see The 'style' атрибут.

The following example shows how the ‘fill’ and ‘stroke’ властивості can be specified on a ‘rect’ using the ‘style’ атрибут. Just like the previous example, the rectangle will be filled with red and outlined with blue:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg" version="1.1"
     width="10cm" height="5cm" viewBox="0 0 1000 500">
  <rect x="200" y="100" width="600" height="300" 
        style="fill: red; stroke: blue; stroke-width: 3"/>
</svg>

View this example as SVG (SVG-enabled browsers only)

In an SVG user agent that supports CSS style sheets, the following facilities from CSS2 must be supported:

CSS2 selectors within style sheets ([CSS2], chapter 5). Because SVG is intended to be used as one component in a multiple namespace XML application and CSS2 is not namespace aware, type selectors will only match against the local part of the елемент's qualified name.
External CSS style sheets [XML-SS], CSS style sheets within ‘style’ елементи and CSS declaration blocks ([CSS2], section 4.1.7) within ‘style’ атрибути attached to specific SVG елементи.
CSS2 rules for assigning властивість values, cascading and inheritance ([CSS2], chapter 6).
@font-face, @media, @import and @charset rules within style sheets ([CSS2], sections 15.3.1, 7.2.1, 6.3 and 4.4).
CSS2's dynamic pseudo-classes :hover, :active and :focus and pseudo-classes :first-child, :visited, :link and :lang ([CSS2], section 5.11). The remaining CSS2 pseudo-classes, including those having to do with generated content ([CSS2], chapter 12), are not part of the SVG language definition. An SVG елемент gains focus when it is selected. See Text selection.
For the purposes of aural media, SVG represents a CSS-stylable XML grammar. In user agents that support aural style sheets, CSS aural style властивості can be applied as defined in CSS2 ([CSS2], chapter 19). (See Aural style sheets.)
CSS style sheets defined within a ‘style’ елемент can be immediate character data content of the ‘style’ елемент or can be embedded within a CDATA section ([XML10], section 2.7).

SVG defines an @color-profile at-rule ([CSS2], section 4.1.6) for defining color profiles so that ICC color profiles can be applied to CSS-styled SVG content.

Note the following about relative URIs and external CSS style sheets: The CSS2 specification says ([CSS2], section 4.3.4) that relative URIs (as defined in Uniform Resource Identifiers (URI): Generic Синтаксис [RFC3986]) within style sheets are resolved such that the base URI is that of the style sheet, not that of the referencing document.

6.7 Case sensitivity of властивість names and values

Property declarations via presentation атрибути are expressed in XML [XML10], which is case-sensitive. CSS властивість declarations specified either in CSS style sheets or in a ‘style’ атрибут, on the other hand, are generally case-insensitive with some exceptions ([CSS2], section 4.1.3).

Because presentation атрибути are expressed as XML атрибути, presentation атрибути are case-sensitive and must match the exact name as specified in the DTD (see the SVG.Presentation.attrib entity in the DTD, which expands to all of the presentation атрибути). When using a presentation атрибут to specify a value for the ‘fill’ властивість, the presentation атрибут must be be specified as fill="…" and not fill="…" or Fill="…". Keyword values, such as italic in font-style="italic", are also case-sensitive and must be specified using the exact case used in the specification which defines the given keyword. For example, the keyword sRGB must have lowercase "s" and uppercase "RGB".

Property declarations within CSS style sheets or in a ‘style’ атрибут must only conform to CSS rules, which are generally more lenient with regard to case sensitivity. Якever, to promote consistency across the different ways for expressing властивості стилю, it is strongly recommended that authors use the exact властивість names (usually, lowercase letters and hyphens) as defined in the relevant specification and express all keywords using the same case as is required by presentation атрибути and not take advantage of CSS's ability to ignore case.

6.8 Facilities from CSS and XSL used by SVG

SVG shares various relevant властивості and approaches common to CSS and XSL, plus the semantics of many of the processing rules.

SVG shares the following facilities with CSS and XSL:

Shared властивості. Many of SVG's властивості are shared between CSS2, XSL and SVG. (See list of shared властивості).
Синтаксис rules. (The normative references are CSS2 syntax and basic типи даних and The grammar of CSS2; in [CSS2], chapter 4 and appendix D.)
Allowable типи даних. (The normative reference is CSS2 syntax and basic типи даних ([CSS2], chapter 4), with the exception that SVG length and angle values without a unit identifier. See Units.)
Inheritance rules.
The color keywords from CSS2 that correspond to the colors used by objects in the user's environment. (The normative reference is CSS2 system colors; in [CSS2], section 18.2.)
For implementations that support CSS styling of SVG content, then that styling must be compatible with various other rules in CSS. (See Styling with CSS.)

6.9 Referencing external style sheets

External style sheets are referenced using the mechanism documented in Associating Style Sheets with XML documents Version 1.0 [XML-SS].

6.10 The ‘style’ елемент

The ‘style’ елемент allows style sheets to be embedded directly within SVG content. SVG's ‘style’ елемент has the same атрибути as the corresponding елемент in HTML (see HTML's ‘style’ елемент).

‘style’

Categories:

None

Content модель:

Any елементи or character data.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
‘type’
‘media’
‘title’

DOM Інтерфейсs:

SVGStyleElement

Attribute definitions:

type = content-type: This атрибут specifies the style sheet language of the елемент's contents. The style sheet language is specified as a content type (e.g., "text/css"), as per MIME Part Two: Media Types [RFC2046]. If a ‘type’ is not provided, the value of ‘contentStyleType’ on the ‘svg’ елемент shall be used, which in turn defaults to "text/css" [RFC2046]. If a ‘style’ елемент falls outside of the outermost svg елемент and the ‘type’ is not provided, the ‘type’ must default to "text/css" [RFC2046].
Animatable: no.
media = media-descriptors: This атрибут specifies the intended destination medium for style information. It may be a single media descriptor or a comma-separated list. The default value for this атрибут is "all". The set of recognized media-descriptors are the list of media types recognized by CSS2 ([CSS2], section 7.3).
Animatable: no.
title = advisory-title: (For compatibility with HTML 4 [HTML4].) This атрибут specifies an advisory title for the ‘style’ елемент.
Animatable: no.

The syntax of style data depends on the style sheet language.

Some style sheet languages might allow a wider variety of rules in the ‘style’ елемент than in the ‘style’. For example, with CSS, rules can be declared within a ‘style’ елемент that cannot be declared within a ‘style’ атрибут.

An example showing the ‘style’ елемент is provided above (see example).

6.11 The ‘class’ атрибут

Attribute definitions:

class = list: This атрибут assigns a class name or set of class names to an елемент. Any number of елементи may be assigned the same class name or names. Multiple class names must be separated by white space characters.
Animatable: yes.

The ‘class’ атрибут assigns one or more class names to an елемент. The елемент may be said to belong to these classes. A class name may be shared by several елемент instances. The ‘class’ атрибут has several roles:

As a style sheet selector (when an author wishes to assign style information to a set of елементи).
For general purpose processing by user agents.

In the following example, the ‘text’ елемент is used in conjunction with the ‘class’ атрибут to markup document messages. Messages appear in both English and French versions.

<!-- English messages -->
<text class="info" lang="en">Variable declared twice</text>
<text class="warning" lang="en">Undeclared variable</text>
<text class="error" lang="en">Bad syntax for variable name</text>
<!-- French messages -->
<text class="info" lang="fr">Variable déclarée deux fois</text>
<text class="warning" lang="fr">Variable indéfinie</text>
<text class="error" lang="fr">Erreur de syntaxe pour variable</text>

In an SVG user agent that supports CSS styling, the following CSS style rules would tell visual user agents to display informational messages in green, warning messages in yellow, and error messages in red:

text.info    { color: green }
text.warning { color: yellow }
text.error   { color: red }

6.12 The ‘style’ атрибут

The ‘style’ атрибут allows per-елемент style rules to be specified directly on a given елемент. When CSS styling is used, CSS inline style is specified by including semicolon-separated властивість declarations of the form "name : value" within the ‘style’ атрибут. Property declarations must follow CSS style rules thus CSS defined властивості (e.g. 'font-size') when having a <length> value must include a unit (for non-zero values). See SVG's властивості стилю for a list of CSS defined властивості.

Attribute definitions:

style = style: This атрибут specifies style information for the current елемент. The style атрибут specifies style information for a single елемент. The style sheet language of inline style rules is given by the value of атрибут ‘contentStyleType’ on the ‘svg’ елемент. The syntax of style data depends on the style sheet language.
Animatable: no.

The style атрибут may be used to apply a particular style to an individual SVG елемент. If the style will be reused for several елементи, authors should use the ‘style’ елемент to regroup that information. For optimal flexibility, authors should define styles in external style sheets.

An example showing the ‘style’ атрибут is provided above (see example).

6.13 Specifying the default style sheet language

The ‘contentStyleType’ атрибут on the ‘svg’ елемент specifies the default style sheet language for the given document fragment.

contentStyleType = "content-type": Identifies the default style sheet language for the given document. That language must then be used for all instances of style that do not specify their own style sheet language, such as the ‘style’ атрибути that are available on many елементи. The value content-type specifies a media type, per MIME Part Two: Media Types [RFC2046]. The default value is "text/css" [RFC2318].
Animatable: no.

Since the only widely deployed language used for inline styling (in style елементи and style атрибути) is CSS, and since that is already the default language if contentStyleType is omitted, in practice contentStyleType is not well supported in user agents. XSL style sheets are typically external. If a new style sheet language becomes popular, it might not use style атрибути and could easily declare which language is in use with the type атрибут on the style елемент.

The use of contentStyleType is therefore deprecated; new content should not use it. Future versions of the SVG specification may remove contentStyleType.

6.14 Property inheritance

Whether or not the user agent supports CSS, властивість inheritance in SVG follows the властивість inheritance rules defined in the CSS2 specification. The normative definition for властивість inheritance is the Inheritance section of the CSS2 specification ([CSS2], section 6.2).

The definition of each властивість indicates whether the властивість can inherit the value of its parent.

In SVG, as in CSS2, most елементи inherit computed values ([CSS2], section 6.1.2). For cases where something other than computed values are inherited, the властивість definition will describe the inheritance rules. For specified values ([CSS2], section 6.1.1) which are expressed in user units, in pixels (e.g., 20px) or in absolute values, the computed value equals the specified value. For specified values which use certain relative units (i.e., em, ex and percentages), the computed value will have the same units as the value to which it is relative. Thus, if the parent елемент has a ‘font-size’ of 10pt and the current елемент has a ‘font-size’ of 120%, then the computed value for ‘font-size’ on the current елемент will be 12pt. In cases where the referenced value for relative units is not expressed in any of the standard SVG units (i.e., CSS units or user units), such as when a percentage is used relative to the current viewport or an object bounding box, then the computed value will be in user units.

Note that SVG has some facilities wherein a властивість which is specified on an ancestor елемент might effect its descendant елемент, even if the descendant елемент has a different assigned value for that властивість. For example, if a ‘clip-path’ властивість is specified on an ancestor елемент, and the current елемент has a ‘clip-path’ of none, the ancestor's clipping path still applies to the current елемент because the semantics of SVG state that the clipping path used on a given елемент is the intersection of all clipping paths specified on itself and all ancestor елементи. The key concept is that властивість assignment (with possible властивість inheritance) happens first. After властивості values have been assigned to the various елементи, then the user agent applies the semantics of each assigned властивість, which might result in the властивість assignment of an ancestor елемент affecting the rendering of its descendants.

6.15 The scope/range of styles

The following define the scope/range of style sheets:

Stand-alone SVG document: There is one parse tree. Style sheets defined anywhere within the SVG document (in style елементи or style атрибути, or in external style sheets linked with the style sheet processing instruction) apply across the entire SVG document.
Stand-alone SVG document embedded in an HTML or XML document with the ‘img’, ‘object’ (HTML) or ‘image’ (SVG) елементи: There are two completely separate parse trees; one for the referencing document (perhaps HTML or XHTML), and one for the SVG document. Style sheets defined anywhere within the referencing document (in style елементи or style атрибути, or in external style sheets linked with the style sheet processing instruction) apply across the entire referencing document but have no effect on the referenced SVG document. Style sheets defined anywhere within the referenced SVG document (in style елементи or style атрибути, or in external style sheets linked with the style sheet processing instruction) apply across the entire SVG document, but do not affect the referencing document (perhaps HTML or XHTML). To get the same styling across both the [X]HTML document and the SVG document, link them both to the same style sheet.
Stand-alone SVG content textually included in an XML document: There is a single parse tree, using multiple namespaces; one or more subtrees are in the SVG namespace. Style sheets defined anywhere within the XML document (in style елементи or style атрибути, or in external style sheets linked with the style sheet processing instruction) apply across the entire document, including those parts of it in the SVG namespace. To get different styling for the SVG part, use the ‘style’ атрибут, or put an ‘id’ on the ‘svg’ елемент and use contextual CSS selectors, or use XSL selectors.

6.16 User agent style sheet

The user agent shall maintain a user agent style sheet ([CSS2], section 6.4) for елементи in the SVG namespace for visual media ([CSS2], section 7.3.1). The user agent style sheet below is expressed using CSS syntax; however, user agents are required to support the behavior that corresponds to this default style sheet even if CSS style sheets are not supported in the user agent:

svg, symbol, image, marker, pattern, foreignObject { overflow: hidden }
svg { width:attr(width); height:attr(height) }

The first line of the above user agent style sheet will cause the initial clipping path to be established at the bounds of the initial viewport. Furthermore, it will cause new clipping paths to be established at the bounds of the listed елементи, all of which are елементи that establish a new viewport. (Refer to the description of SVG's use of the ‘overflow’ властивість for more information.)

The second line of the above user agent style sheet will cause the ‘width’ and ‘height’ атрибути on the ‘svg’ елемент to be used as the default values for the 'width' and 'height' властивості during layout ([CSS2], chapter 9).

6.17 Aural style sheets

For the purposes of aural media, SVG represents a stylable XML grammar. In user agents that support CSS aural style sheets, aural style властивості ([CSS2], chapter 19) can be applied as defined in CSS2.

Aural style властивості can be applied to any SVG елемент that can contain character data content, including ‘desc’ ‘title’ ‘tspan’, ‘tref’, ‘altGlyph’ and ‘textPath’. On user agents that support aural style sheets, the following CSS2 властивості can be applied:

Aural властивість	Definition in [CSS2]
‘azimuth’	Section 19.7
‘cue’	Section 19.5
‘cue-after’	Section 19.5
‘cue-before’	Section 19.5
‘elevation’	Section 19.7
‘pause’	Section 19.4
‘pause-after’	Section 19.4
‘pause-before’	Section 19.4
‘pitch’	Section 19.8
‘pitch-range’	Section 19.8
‘play-during’	Section 19.6
‘richness’	Section 19.8
‘speak’	Section 19.3
‘speak-header’	Section 17.7.1
‘speak-numeral’	Section 19.9
‘speak-punctuation’	Section 19.9
‘speech-rate’	Section 19.8
‘stress’	Section 19.8
‘voice-family’	Section 19.8
‘volume’	Section 19.2

For user agents that support aural style sheets and also support DOM Level 2 Core [DOM2], the user agent is required to support the DOM interfaces defined in Document Object Model CSS ([DOM2STYLE], chapter 2) that correspond to aural властивості. (See Relationship with DOM2 CSS object модель.)

6.18 DOM interfaces

6.18.1 Інтерфейс SVGStyleElement

The SVGStyleElement interface corresponds to the ‘style’ елемент.

interface SVGStyleElement : SVGElement,
                            SVGLangSpace {
  атрибут DOMString type setraises(DOMException);
  атрибут DOMString media setraises(DOMException);
  атрибут DOMString title setraises(DOMException);
};

Attributes:

type (DOMString)

Corresponds to атрибут ‘type’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

media (DOMString)

Corresponds to атрибут ‘media’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

title (DOMString)

Corresponds to атрибут ‘title’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

7 Coordinate Systems, Transformations and Units

7.1 Вступ
7.2 The initial viewport
7.3 The initial coordinate system
7.4 Coordinate system transformations
7.5 Nested transformations
7.6 The ‘transform’ атрибут
7.7 The ‘viewBox’ атрибут
7.8 The ‘preserveAspectRatio’ атрибут
7.9 Establishing a new viewport
7.10 Units
7.11 Object bounding box units
7.12 Intrinsic sizing властивості of the viewport of SVG content
7.13 Geographic coordinate systems
7.14 The ‘svg:transform’ атрибут
7.15 DOM interfaces

7.1 Вступ

For all media, the SVG canvas describes "the space where the SVG content is rendered." The canvas is infinite for each dimension of the space, but rendering occurs relative to a finite rectangular region of the canvas. This finite rectangular region is called the SVG viewport. For visual media ([CSS2], section 7.3.1) the SVG viewport is the viewing area where the user sees the SVG content.

The size of the SVG viewport (i.e., its width and height) is determined by a negotiation process (see Establishing the size of the initial viewport) between the SVG document fragment and its parent (real or implicit). Once that negotiation process is completed, the SVG user agent is provided the following information:

a number (usually an integer) that represents the width in "pixels" of the viewport
a number (usually an integer) that represents the height in "pixels" of the viewport
(highly desirable but not required) a real number value that indicates the size in real world units, such as millimeters, of a "pixel" (i.e., a px unit as defined in CSS2 ([CSS2], section 4.3.2)

Using the above information, the SVG user agent determines the viewport, an initial viewport coordinate system and an initial user coordinate system such that the two coordinates systems are identical. Both coordinates systems are established such that the origin matches the origin of the viewport (for the root viewport, the viewport origin is at the top/left corner), and one unit in the initial coordinate system equals one "pixel" in the viewport. (See Initial coordinate system.) The viewport coordinate system is also called viewport space and the user coordinate system is also called user space.

Lengths in SVG can be specified as:

(if no unit identifier is provided) values in user space — for example, "15"
(if a unit identifier is provided) a length expressed as an absolute or relative unit measure — for example, "15mm" or "5em"

The supported length unit identifiers are: em, ex, px, pt, pc, cm, mm, in, and percentages.

A new user space (i.e., a new current coordinate system) can be established at any place within an SVG document fragment by specifying transformations in the form of transformation matrices or simple transformation operations such as rotation, skewing, scaling and translation. Establishing new user spaces via coordinate system transformations are fundamental operations to 2D graphics and represent the usual method of controlling the size, position, rotation and skew of graphic objects.

New viewports also can be established. By establishing a new viewport, you can redefine the meaning of percentages units and provide a new reference rectangle for "fitting" a graphic into a particular rectangular area. ("Fit" means that a given graphic is transformed in such a way that its bounding box in user space aligns exactly with the edges of a given viewport.)

7.2 The initial viewport

The SVG user agent negotiates with its parent user agent to determine the viewport into which the SVG user agent can render the document. In some circumstances, SVG content will be embedded (by reference or inline) within a containing document. This containing document might include атрибути, властивості and/or other parameters (explicit or implicit) which specify or provide hints about the dimensions of the viewport for the SVG content. SVG content itself optionally can provide information about the appropriate viewport region for the content via the ‘width’ and ‘height’ XML атрибути on the outermost svg елемент. The negotiation process uses any information provided by the containing document and the SVG content itself to choose the viewport location and size.

The ‘width’ атрибут on the outermost svg елемент establishes the viewport's width, unless the following conditions are met:

the SVG content is a separately stored resource that is embedded by reference (such as the ‘object’ елемент in XHTML [XHTML]), or the SVG content is embedded inline within a containing document;
and the referencing елемент or containing document is styled using CSS [CSS2] or XSL [XSL];
and there are CSS-compatible positioning властивості ([CSS2], section 9.3) specified on the referencing елемент (e.g., the ‘object’ елемент) or on the containing document's outermost svg елемент that are sufficient to establish the width of the viewport.

Under these conditions, the positioning властивості establish the viewport's width.

Similarly, if there are positioning властивості specified on the referencing елемент or on the outermost svg елемент that are sufficient to establish the height of the viewport, then these positioning властивості establish the viewport's height; otherwise, the ‘height’ атрибут on the outermost svg елемент establishes the viewport's height.

If the ‘width’ or ‘height’ атрибути on the outermost svg елемент are in user units (i.e., no unit identifier has been provided), then the value is assumed to be equivalent to the same number of "px" units (see Units).

In the following example, an SVG graphic is embedded inline within a parent XML document which is formatted using CSS layout rules. Since CSS positioning властивості are not provided on the outermost svg елемент, the width="100px" and height="200px" атрибути determine the size of the initial viewport:

<?xml version="1.0" standalone="yes"?>
<parent xmlns="http://some.url">
   
   <!-- SVG graphic -->
   <svg xmlns='http://www.w3.org/2000/svg'
      width="100px" height="200px" version="1.1">
      <path d="M100,100 Q200,400,300,100"/>
      <!-- rest of SVG graphic would go here -->
   </svg>   
   
</parent>

The initial clipping path for the SVG document fragment is established according to the rules described in The initial clipping path.

7.3 The initial coordinate system

For the outermost svg елемент, the SVG user agent determines an initial viewport coordinate system and an initial user coordinate system such that the two coordinates systems are identical. The origin of both coordinate systems is at the origin of the viewport, and one unit in the initial coordinate system equals one "pixel" (i.e., a px unit as defined in CSS2 ([CSS2], section 4.3.2) in the viewport. In most cases, such as stand-alone SVG documents or SVG document fragments embedded (by reference or inline) within XML parent documents where the parent's layout is determined by CSS [CSS2] or XSL [XSL], the initial viewport coordinate system (and therefore the initial user coordinate system) has its origin at the top/left of the viewport, with the positive x-axis pointing towards the right, the positive y-axis pointing down, and text rendered with an "upright" orientation, which means glyphs are oriented such that Roman characters and full-size ideographic characters for Asian scripts have the top edge of the corresponding glyphs oriented upwards and the right edge of the corresponding glyphs oriented to the right.

If the SVG implementation is part of a user agent which supports styling XML documents using CSS2 compatible px units, then the SVG user agent should get its initial value for the size of a px unit in real world units to match the value used for other XML styling operations; otherwise, if the user agent can determine the size of a px unit from its environment, it should use that value; otherwise, it should choose an appropriate size for one px unit. In all cases, the size of a px must be in conformance with the rules described in CSS2 ([CSS2], section 4.3.2).

Example InitialCoords below shows that the initial coordinate system has the origin at the top/left with the x-axis pointing to the right and the y-axis pointing down. The initial user coordinate system has one user unit equal to the parent (implicit or explicit) user agent's "pixel".

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="300px" height="100px" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>Example InitialCoords - SVG's initial coordinate system</desc>

  <g fill="none" stroke="black" stroke-width="3" >
    <line x1="0" y1="1.5" x2="300" y2="1.5" />
    <line x1="1.5" y1="0" x2="1.5" y2="100" />
  </g>
  <g fill="red" stroke="none" >
    <rect x="0" y="0" width="3" height="3" />
    <rect x="297" y="0" width="3" height="3" />
    <rect x="0" y="97" width="3" height="3" />
  </g>
  <g font-size="14" font-family="Verdana" >
    <text x="10" y="20">(0,0)</text>
    <text x="240" y="20">(300,0)</text>
    <text x="10" y="90">(0,100)</text>
  </g>
</svg>

Example InitialCoords

View this example as SVG (SVG-enabled browsers only)

7.4 Coordinate system transformations

A new user space (i.e., a new current coordinate system) can be established by specifying transformations in the form of a ‘transform’ атрибут on a container елемент or graphics елемент or a ‘viewBox’ атрибут on an ‘svg’, ‘symbol’, ‘marker’, ‘pattern’ and the ‘view’ елемент. The ‘transform’ and ‘viewBox’ атрибути transform user space coordinates and lengths on sibling атрибути on the given елемент (see effect of the ‘transform’ атрибут on sibling атрибути and effect of the ‘viewBox’ атрибут on sibling атрибути) and all of its descendants. Transformations can be nested, in which case the effect of the transformations are cumulative.

Example OrigCoordSys below shows a document without transformations. The text string is specified in the initial coordinate system.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="400px" height="150px"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example OrigCoordSys - Simple transformations: original picture</desc>
  <g fill="none" stroke="black" stroke-width="3" >
    <!-- Draw the axes of the original coordinate system -->
    <line x1="0" y1="1.5" x2="400" y2="1.5" />
    <line x1="1.5" y1="0" x2="1.5" y2="150" />
  </g>
  <g>
    <text x="30" y="30" font-size="20" font-family="Verdana" >
      ABC (orig coord system)
    </text>
  </g>
</svg>

Example OrigCoordSys

View this example as SVG (SVG-enabled browsers only)

Example NewCoordSys establishes a new user coordinate system by specifying transform="translate(50,50)" on the third ‘g’ елемент below. The new user coordinate system has its origin at location (50,50) in the original coordinate system. The result of this transformation is that the coordinate (30,30) in the new user coordinate system gets mapped to coordinate (80,80) in the original coordinate system (i.e., the coordinates have been translated by 50 units in X and 50 units in Y).

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="400px" height="150px"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example NewCoordSys - New user coordinate system</desc>
  <g fill="none" stroke="black" stroke-width="3" >
    <!-- Draw the axes of the original coordinate system -->
    <line x1="0" y1="1.5" x2="400" y2="1.5" />
    <line x1="1.5" y1="0" x2="1.5" y2="150" />
  </g>
  <g>
    <text x="30" y="30" font-size="20" font-family="Verdana" >
      ABC (orig coord system)
    </text>
  </g>
  <!-- Establish a new coordinate system, which is
       shifted (i.e., translated) from the initial coordinate
       system by 50 user units along each axis. -->
  <g transform="translate(50,50)">
    <g fill="none" stroke="red" stroke-width="3" >
      <!-- Draw lines of length 50 user units along 
           the axes of the new coordinate system -->
      <line x1="0" y1="0" x2="50" y2="0" stroke="red" />
      <line x1="0" y1="0" x2="0" y2="50" />
    </g>
    <text x="30" y="30" font-size="20" font-family="Verdana" >
      ABC (translated coord system)
    </text>
  </g>
</svg>

Example NewCoordSys

View this example as SVG (SVG-enabled browsers only)

Example RotateScale illustrates simple rotate and scale transformations. The example defines two new coordinate systems:

one which is the result of a translation by 50 units in X and 30 units in Y, followed by a rotation of 30 degrees
another which is the result of a translation by 200 units in X and 40 units in Y, followed by a scale transformation of 1.5.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="400px" height="120px" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>Example RotateScale - Rotate and scale transforms</desc>
  <g fill="none" stroke="black" stroke-width="3" >
    <!-- Draw the axes of the original coordinate system -->
    <line x1="0" y1="1.5" x2="400" y2="1.5" />
    <line x1="1.5" y1="0" x2="1.5" y2="120" />
  </g>
  <!-- Establish a new coordinate system whose origin is at (50,30)
       in the initial coord. system and which is rotated by 30 degrees. -->
  <g transform="translate(50,30)">
    <g transform="rotate(30)">
      <g fill="none" stroke="red" stroke-width="3" >
        <line x1="0" y1="0" x2="50" y2="0" />
        <line x1="0" y1="0" x2="0" y2="50" />
      </g>
      <text x="0" y="0" font-size="20" font-family="Verdana" fill="blue" >
        ABC (rotate)
      </text>
    </g>
  </g>
  <!-- Establish a new coordinate system whose origin is at (200,40)
       in the initial coord. system and which is scaled by 1.5. -->
  <g transform="translate(200,40)">
    <g transform="scale(1.5)">
      <g fill="none" stroke="red" stroke-width="3" >
        <line x1="0" y1="0" x2="50" y2="0" />
        <line x1="0" y1="0" x2="0" y2="50" />
      </g>
      <text x="0" y="0" font-size="20" font-family="Verdana" fill="blue" >
        ABC (scale)
      </text>
    </g>
  </g>
</svg>

Example RotateScale

View this example as SVG (SVG-enabled browsers only)

Example Skew defines two coordinate systems which are skewed relative to the origin coordinate system.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="400px" height="120px" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>Example Skew - Show effects of skewX and skewY</desc>
  <g fill="none" stroke="black" stroke-width="3" >
    <!-- Draw the axes of the original coordinate system -->
    <line x1="0" y1="1.5" x2="400" y2="1.5" />
    <line x1="1.5" y1="0" x2="1.5" y2="120" />
  </g>
  <!-- Establish a new coordinate system whose origin is at (30,30)
       in the initial coord. system and which is skewed in X by 30 degrees. -->
  <g transform="translate(30,30)">
    <g transform="skewX(30)">
      <g fill="none" stroke="red" stroke-width="3" >
        <line x1="0" y1="0" x2="50" y2="0" />
        <line x1="0" y1="0" x2="0" y2="50" />
      </g>
      <text x="0" y="0" font-size="20" font-family="Verdana" fill="blue" >
        ABC (skewX)
      </text>
    </g>
  </g>
  <!-- Establish a new coordinate system whose origin is at (200,30)
       in the initial coord. system and which is skewed in Y by 30 degrees. -->
  <g transform="translate(200,30)">
    <g transform="skewY(30)">
      <g fill="none" stroke="red" stroke-width="3" >
        <line x1="0" y1="0" x2="50" y2="0" />
        <line x1="0" y1="0" x2="0" y2="50" />
      </g>
      <text x="0" y="0" font-size="20" font-family="Verdana" fill="blue" >
        ABC (skewY)
      </text>
    </g>
  </g>
</svg>

Example Skew

View this example as SVG (SVG-enabled browsers only)

Mathematically, all transformations can be represented as 3x3 transformation matrices of the following form:
3-by-3 transformation matrix

Since only six values are used in the above 3x3 matrix, a transformation matrix is also expressed as a vector: [a b c d e f].

Transformations map coordinates and lengths from a new coordinate system into a previous coordinate system:
3-by-3 transformation matrix

Simple transformations are represented in matrix form as follows:

Translation is equivalent to the matrix

or [1 0 0 1 tx ty], where tx and ty are the distances to translate coordinates in X and Y, respectively.
Scaling is equivalent to the matrix

or [sx 0 0 sy 0 0]. One unit in the X and Y directions in the new coordinate system equals sx and sy units in the previous coordinate system, respectively.
Rotation about the origin is equivalent to the matrix

or [cos(a) sin(a) -sin(a) cos(a) 0 0], which has the effect of rotating the coordinate system axes by angle a.
A skew transformation along the x-axis is equivalent to the matrix

or [1 0 tan(a) 1 0 0], which has the effect of skewing X coordinates by angle a.
A skew transformation along the y-axis is equivalent to the matrix

or [1 tan(a) 0 1 0 0], which has the effect of skewing Y coordinates by angle a.

7.5 Nested transformations

Transformations can be nested to any level. The effect of nested transformations is to post-multiply (i.e., concatenate) the subsequent transformation matrices onto previously defined transformations:
3-by-3 matrix concatenation

For each given елемент, the accumulation of all transformations that have been defined on the given елемент and all of its ancestors up to and including the елемент that established the current viewport (usually, the ‘svg’ елемент which is the most immediate ancestor to the given елемент) is called the current transformation matrix or CTM. The CTM thus represents the mapping of current user coordinates to viewport coordinates:
current transformation matrix: CTM

Example Nested illustrates nested transformations.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="400px" height="150px" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>Example Nested - Nested transformations</desc>
  <g fill="none" stroke="black" stroke-width="3" >
    <!-- Draw the axes of the original coordinate system -->
    <line x1="0" y1="1.5" x2="400" y2="1.5" />
    <line x1="1.5" y1="0" x2="1.5" y2="150" />
  </g>
  <!-- First, a translate -->
  <g transform="translate(50,90)">
    <g fill="none" stroke="red" stroke-width="3" >
      <line x1="0" y1="0" x2="50" y2="0" />
      <line x1="0" y1="0" x2="0" y2="50" />
    </g>
    <text x="0" y="0" font-size="16" font-family="Verdana" >
      ....Translate(1)
    </text>
    <!-- Second, a rotate -->
    <g transform="rotate(-45)">
      <g fill="none" stroke="green" stroke-width="3" >
        <line x1="0" y1="0" x2="50" y2="0" />
        <line x1="0" y1="0" x2="0" y2="50" />
      </g>
      <text x="0" y="0" font-size="16" font-family="Verdana" >
        ....Rotate(2)
      </text>
      <!-- Third, another translate -->
      <g transform="translate(130,160)">
        <g fill="none" stroke="blue" stroke-width="3" >
          <line x1="0" y1="0" x2="50" y2="0" />
          <line x1="0" y1="0" x2="0" y2="50" />
        </g>
        <text x="0" y="0" font-size="16" font-family="Verdana" >
          ....Translate(3)
        </text>
      </g>
    </g>
  </g>
</svg>

Example Nested

View this example as SVG (SVG-enabled browsers only)

In the example above, the CTM within the third nested transformation (i.e., the transform="translate(130,160)") consists of the concatenation of the three transformations, as follows:
Matrix concatenation

7.6 The ‘transform’ атрибут

The value of the ‘transform’ атрибут is a <transform-list>, which is defined as a list of transform definitions, which are applied in the order provided. The individual transform definitions are separated by whitespace and/or a comma. The available types of transform definitions include:

matrix(<a> <b> <c> <d> <e> <f>), which specifies a transformation in the form of a transformation matrix of six values. matrix(a,b,c,d,e,f) is equivalent to applying the transformation matrix [a b c d e f].
translate(<tx> [<ty>]), which specifies a translation by tx and ty. If <ty> is not provided, it is assumed to be zero.
scale(<sx> [<sy>]), which specifies a scale operation by sx and sy. If <sy> is not provided, it is assumed to be equal to <sx>.
rotate(<rotate-angle> [<cx> <cy>]), which specifies a rotation by <rotate-angle> degrees about a given point.
If optional parameters <cx> and <cy> are not supplied, the rotate is about the origin of the current user coordinate system. The operation corresponds to the matrix [cos(a) sin(a) -sin(a) cos(a) 0 0].
If optional parameters <cx> and <cy> are supplied, the rotate is about the point (cx, cy). The operation represents the equivalent of the following specification: translate(<cx>, <cy>) rotate(<rotate-angle>) translate(-<cx>, -<cy>).
skewX(<skew-angle>), which specifies a skew transformation along the x-axis.
skewY(<skew-angle>), which specifies a skew transformation along the y-axis.

All numeric values are <number>s.

If a list of transforms is provided, then the net effect is as if each transform had been specified separately in the order provided. For example,

<g transform="translate(-10,-20) scale(2) rotate(45) translate(5,10)">
  <!-- graphics елементи go here -->
</g>

is functionally equivalent to:

<g transform="translate(-10,-20)">
  <g transform="scale(2)">
    <g transform="rotate(45)">
      <g transform="translate(5,10)">
        <!-- graphics елементи go here -->
      </g>
    </g>
  </g>
</g>

The ‘transform’ атрибут is applied to an елемент before processing any other coordinate or length values supplied for that елемент. In the елемент

<rect x="10" y="10" width="20" height="20" transform="scale(2)"/>

the x, y, width and height values are processed after the current coordinate system has been scaled uniformly by a factor of 2 by the ‘transform’ атрибут. Attributes x, y, width and height (and any other атрибути or властивості) are treated as values in the new user coordinate system, not the previous user coordinate system. Thus, the above ‘rect’ елемент is functionally equivalent to:

<g transform="scale(2)">
  <rect x="10" y="10" width="20" height="20"/>
</g>

The following is the Backus-Naur Form (BNF) for values for the ‘transform’ атрибут. The following notation is used:

*: 0 or more
+: 1 or more
?: 0 or 1
(): grouping
|: separates alternatives
double quotes surround literals

transform-list:
    wsp* transforms? wsp*
transforms:
    transform
    | transform comma-wsp+ transforms
transform:
    matrix
    | translate
    | scale
    | rotate
    | skewX
    | skewY
matrix:
    "matrix" wsp* "(" wsp*
       number comma-wsp
       number comma-wsp
       number comma-wsp
       number comma-wsp
       number comma-wsp
       number wsp* ")"
translate:
    "translate" wsp* "(" wsp* number ( comma-wsp number )? wsp* ")"
scale:
    "scale" wsp* "(" wsp* number ( comma-wsp number )? wsp* ")"
rotate:
    "rotate" wsp* "(" wsp* number ( comma-wsp number comma-wsp number )? wsp* ")"
skewX:
    "skewX" wsp* "(" wsp* number wsp* ")"
skewY:
    "skewY" wsp* "(" wsp* number wsp* ")"
number:
    sign? integer-constant
    | sign? floating-point-constant
comma-wsp:
    (wsp+ comma? wsp*) | (comma wsp*)
comma:
    ","
integer-constant:
    digit-sequence
floating-point-constant:
    fractional-constant exponent?
    | digit-sequence exponent
fractional-constant:
    digit-sequence? "." digit-sequence
    | digit-sequence "."
exponent:
    ( "e" | "E" ) sign? digit-sequence
sign:
    "+" | "-"
digit-sequence:
    digit
    | digit digit-sequence
digit:
    "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
wsp:
    (#x20 | #x9 | #xD | #xA)

For the ‘transform’ атрибут:

Animatable: yes.

See the ‘animateTransform’ елемент for information on animating transformations.

7.7 The ‘viewBox’ атрибут

It is often desirable to specify that a given set of graphics stretch to fit a particular container елемент. The ‘viewBox’ атрибут provides this capability.

All елементи that establish a new viewport (see елементи that establish viewports), plus the ‘marker’, ‘pattern’ and ‘view’ елементи have атрибут ‘viewBox’. The value of the ‘viewBox’ атрибут is a list of four numbers <min-x>, <min-y>, <width> and <height>, separated by whitespace and/or a comma, which specify a rectangle in user space which should be mapped to the bounds of the viewport established by the given елемент, taking into account атрибут ‘preserveAspectRatio’. If specified, an additional transformation is applied to all descendants of the given елемент to achieve the specified effect.

A negative value for <width> or <height> is an error (see Error processing). A value of zero disables rendering of the елемент.

Example ViewBox illustrates the use of the ‘viewBox’ атрибут on the outermost svg елемент to specify that the SVG content should stretch to fit bounds of the viewport.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="300px" height="200px" version="1.1"
     viewBox="0 0 1500 1000" preserveAspectRatio="none"
     xmlns="http://www.w3.org/2000/svg">
  <desc>Example ViewBox - uses the viewBox 
   атрибут to automatically create an initial user coordinate
   system which causes the graphic to scale to fit into the
   viewport no matter what size the viewport is.</desc>
  <!-- This rectangle goes from (0,0) to (1500,1000) in user space.
       Because of the viewBox атрибут above,
       the rectangle will end up filling the entire area
       reserved for the SVG content. -->
  <rect x="0" y="0" width="1500" height="1000" 
        fill="yellow" stroke="blue" stroke-width="12"  />
  <!-- A large, red triangle -->
  <path fill="red"  d="M 750,100 L 250,900 L 1250,900 z"/>
  <!-- A text string that spans most of the viewport -->
  <text x="100" y="600" font-size="200" font-family="Verdana" >
    Stretch to fit
  </text>
</svg>

Example ViewBox
Rendered into viewport with width=300px, height=200px		Rendered into viewport with width=150px, height=200px

View this example as SVG (SVG-enabled browsers only)

The effect of the ‘viewBox’ атрибут is that the user agent automatically supplies the appropriate transformation matrix to map the specified rectangle in user space to the bounds of a designated region (often, the viewport). To achieve the effect of the example on the left, with viewport dimensions of 300 by 200 pixels, the user agent needs to automatically insert a transformation which scales both X and Y by 0.2. The effect is equivalent to having a viewport of size 300px by 200px and the following supplemental transformation in the document, as follows:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="300px" height="200px" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <g transform="scale(0.2)">
    <!-- Rest of document goes here -->
  </g>
</svg>

To achieve the effect of the example on the right, with viewport dimensions of 150 by 200 pixels, the user agent needs to automatically insert a transformation which scales X by 0.1 and Y by 0.2. The effect is equivalent to having a viewport of size 150px by 200px and the following supplemental transformation in the document, as follows:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="150px" height="200px" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <g transform="scale(0.1 0.2)">
    <!-- Rest of document goes here -->
  </g>
</svg>

(Note: in some cases the user agent will need to supply a translate transformation in addition to a scale transformation. For example, on an outermost svg елемент, a translate transformation will be needed if the ‘viewBox’ атрибути specifies values other than zero for <min-x> or <min-y>.)

Unlike the ‘transform’ атрибут (see effect of the ‘transform’ on sibling атрибути), the automatic transformation that is created due to a ‘viewBox’ does not affect the ‘x’, ‘y’, ‘width’ and ‘height’ атрибути (or in the case of the ‘marker’ елемент, the ‘markerWidth’ and ‘markerHeight’ атрибути) on the елемент with the ‘viewBox’ атрибут. Thus, in the example above which shows an ‘svg’ елемент which has атрибути ‘width’, ‘height’ and ‘viewBox’, the ‘width’ and ‘height’ атрибути represent values in the coordinate system that exists before the ‘viewBox’ transformation is applied. On the other hand, like the ‘transform’ атрибут, it does establish a new coordinate system for all other атрибути and for descendant елементи.

For the ‘viewBox’ атрибут:

Animatable: yes.

7.8 The ‘preserveAspectRatio’ атрибут

In some cases, typically when using the ‘viewBox’ атрибут, it is desirable that the graphics stretch to fit non-uniformly to take up the entire viewport. In other cases, it is desirable that uniform scaling be used for the purposes of preserving the aspect ratio of the graphics.

Attribute preserveAspectRatio="[defer] <align> [<meetOrSlice>]", which is available for all елементи that establish a new viewport (see елементи that establish viewports), plus the ‘image’, ‘marker’, ‘pattern’ and ‘view’ елементи, indicates whether or not to force uniform scaling.

For елементи that establish a new viewport (see елементи that establish viewports), plus the ‘marker’, ‘pattern’ and ‘view’ елементи, ‘preserveAspectRatio’ only applies when a value has been provided for ‘viewBox’ on the same елемент. For these елементи, if атрибут ‘viewBox’ is not provided, then ‘preserveAspectRatio’ is ignored.

For ‘image’ елементи, ‘preserveAspectRatio’ indicates how referenced images should be fitted with respect to the reference rectangle and whether the aspect ratio of the referenced image should be preserved with respect to the current user coordinate system.

If the value of ‘preserveAspectRatio’ on an ‘image’ елемент starts with 'defer' then the value of the ‘preserveAspectRatio’ атрибут on the referenced content if present should be used. If the referenced content lacks a value for ‘preserveAspectRatio’ then the ‘preserveAspectRatio’ атрибут should be processed as normal (ignoring 'defer'). For ‘preserveAspectRatio’ on all other елементи the 'defer' portion of the атрибут is ignored.

The <align> parameter indicates whether to force uniform scaling and, if so, the alignment method to use in case the aspect ratio of the ‘viewBox’ doesn't match the aspect ratio of the viewport. The <align> parameter must be one of the following strings:

none - Do not force uniform scaling. Scale the graphic content of the given елемент non-uniformly if necessary such that the елемент's bounding box exactly matches the viewport rectangle.
(Note: if <align> is none, then the optional <meetOrSlice> value is ignored.)
xMinYMin - Force uniform scaling.
Align the <min-x> of the елемент's ‘viewBox’ with the smallest X value of the viewport.
Align the <min-y> of the елемент's ‘viewBox’ with the smallest Y value of the viewport.
xMidYMin - Force uniform scaling.
Align the midpoint X value of the елемент's ‘viewBox’ with the midpoint X value of the viewport.
Align the <min-y> of the елемент's ‘viewBox’ with the smallest Y value of the viewport.
xMaxYMin - Force uniform scaling.
Align the <min-x>+<width> of the елемент's ‘viewBox’ with the maximum X value of the viewport.
Align the <min-y> of the елемент's ‘viewBox’ with the smallest Y value of the viewport.
xMinYMid - Force uniform scaling.
Align the <min-x> of the елемент's ‘viewBox’ with the smallest X value of the viewport.
Align the midpoint Y value of the елемент's ‘viewBox’ with the midpoint Y value of the viewport.
xMidYMid (the default) - Force uniform scaling.
Align the midpoint X value of the елемент's ‘viewBox’ with the midpoint X value of the viewport.
Align the midpoint Y value of the елемент's ‘viewBox’ with the midpoint Y value of the viewport.
xMaxYMid - Force uniform scaling.
Align the <min-x>+<width> of the елемент's ‘viewBox’ with the maximum X value of the viewport.
Align the midpoint Y value of the елемент's ‘viewBox’ with the midpoint Y value of the viewport.
xMinYMax - Force uniform scaling.
Align the <min-x> of the елемент's ‘viewBox’ with the smallest X value of the viewport.
Align the <min-y>+<height> of the елемент's ‘viewBox’ with the maximum Y value of the viewport.
xMidYMax - Force uniform scaling.
Align the midpoint X value of the елемент's ‘viewBox’ with the midpoint X value of the viewport.
Align the <min-y>+<height> of the елемент's ‘viewBox’ with the maximum Y value of the viewport.
xMaxYMax - Force uniform scaling.
Align the <min-x>+<width> of the елемент's ‘viewBox’ with the maximum X value of the viewport.
Align the <min-y>+<height> of the елемент's ‘viewBox’ with the maximum Y value of the viewport.

The <meetOrSlice> parameter is optional and, if provided, is separated from the <align> value by one or more spaces and then must be one of the following strings:

meet (the default) - Scale the graphic such that:
- aspect ratio is preserved
- the entire ‘viewBox’ is visible within the viewport
- the ‘viewBox’ is scaled up as much as possible, while still meeting the other criteria
In this case, if the aspect ratio of the graphic does not match the viewport, some of the viewport will extend beyond the bounds of the ‘viewBox’ (i.e., the area into which the ‘viewBox’ will draw will be smaller than the viewport).
slice - Scale the graphic such that:
- aspect ratio is preserved
- the entire viewport is covered by the ‘viewBox’
- the ‘viewBox’ is scaled down as much as possible, while still meeting the other criteria
In this case, if the aspect ratio of the ‘viewBox’ does not match the viewport, some of the ‘viewBox’ will extend beyond the bounds of the viewport (i.e., the area into which the ‘viewBox’ will draw is larger than the viewport).

Example PreserveAspectRatio illustrates the various options on ‘preserveAspectRatio’. To save space, XML entities have been defined for the three repeated graphic objects, the rectangle with the smile inside and the outlines of the two rectangles which have the same dimensions as the target viewports. The example creates several new viewports by including ‘svg’ sub-елементи embedded inside the outermost svg елемент (see Establishing a new viewport).

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"
[ <!ENTITY Smile "
<rect x='.5' y='.5' width='29' height='39' fill='black' stroke='red'/>
<g transform='translate(0, 5)'>
<circle cx='15' cy='15' r='10' fill='yellow'/>
<circle cx='12' cy='12' r='1.5' fill='black'/>
<circle cx='17' cy='12' r='1.5' fill='black'/>
<path d='M 10 19 A 8 8 0 0 0 20 19' stroke='black' stroke-width='2'/>
</g>
">
<!ENTITY Viewport1 "<rect x='.5' y='.5' width='49' height='29'
fill='none' stroke='blue'/>">
<!ENTITY Viewport2 "<rect x='.5' y='.5' width='29' height='59'
fill='none' stroke='blue'/>">
]>

<svg width="450px" height="300px" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>Example PreserveAspectRatio - illustrates preserveAspectRatio атрибут</desc>
  <rect x="1" y="1" width="448" height="298"
        fill="none" stroke="blue"/>
  <g font-size="9">
    <text x="10" y="30">SVG to fit</text>
    <g transform="translate(20,40)">&Smile;</g>
    <text x="10" y="110">Viewport 1</text>
    <g transform="translate(10,120)">&Viewport1;</g>
    <text x="10" y="180">Viewport 2</text>
    <g transform="translate(20,190)">&Viewport2;</g>

    <g id="meet-group-1" transform="translate(100, 60)">
      <text x="0" y="-30">--------------- meet ---------------</text>
      <g><text y="-10">xMin*</text>&Viewport1;
        <svg preserveAspectRatio="xMinYMin meet" viewBox="0 0 30 40"
             width="50" height="30">&Smile;</svg></g>
      <g transform="translate(70,0)"><text y="-10">xMid*</text>&Viewport1;
        <svg preserveAspectRatio="xMidYMid meet" viewBox="0 0 30 40"
             width="50" height="30">&Smile;</svg></g>
      <g transform="translate(0,70)"><text y="-10">xMax*</text>&Viewport1;
        <svg preserveAspectRatio="xMaxYMax meet" viewBox="0 0 30 40"
             width="50" height="30">&Smile;</svg></g>
    </g>

    <g id="meet-group-2" transform="translate(250, 60)">
      <text x="0" y="-30">---------- meet ----------</text>
      <g><text y="-10">*YMin</text>&Viewport2;
        <svg preserveAspectRatio="xMinYMin meet" viewBox="0 0 30 40"
             width="30" height="60">&Smile;</svg></g>
      <g transform="translate(50, 0)"><text y="-10">*YMid</text>&Viewport2;
        <svg preserveAspectRatio="xMidYMid meet" viewBox="0 0 30 40"
             width="30" height="60">&Smile;</svg></g>
      <g transform="translate(100, 0)"><text y="-10">*YMax</text>&Viewport2;
        <svg preserveAspectRatio="xMaxYMax meet" viewBox="0 0 30 40"
             width="30" height="60">&Smile;</svg></g>
    </g>

    <g id="slice-group-1" transform="translate(100, 220)">
      <text x="0" y="-30">---------- slice ----------</text>
      <g><text y="-10">xMin*</text>&Viewport2;
        <svg preserveAspectRatio="xMinYMin slice" viewBox="0 0 30 40"
             width="30" height="60">&Smile;</svg></g>
      <g transform="translate(50,0)"><text y="-10">xMid*</text>&Viewport2;
        <svg preserveAspectRatio="xMidYMid slice" viewBox="0 0 30 40"
             width="30" height="60">&Smile;</svg></g>
      <g transform="translate(100,0)"><text y="-10">xMax*</text>&Viewport2;
        <svg preserveAspectRatio="xMaxYMax slice" viewBox="0 0 30 40"
             width="30" height="60">&Smile;</svg></g>
    </g>

    <g id="slice-group-2" transform="translate(250, 220)">
      <text x="0" y="-30">--------------- slice ---------------</text>
      <g><text y="-10">*YMin</text>&Viewport1;
        <svg preserveAspectRatio="xMinYMin slice" viewBox="0 0 30 40"
             width="50" height="30">&Smile;</svg></g>
      <g transform="translate(70,0)"><text y="-10">*YMid</text>&Viewport1;
        <svg preserveAspectRatio="xMidYMid slice" viewBox="0 0 30 40"
             width="50" height="30">&Smile;</svg></g>
      <g transform="translate(140,0)"><text y="-10">*YMax</text>&Viewport1;
        <svg preserveAspectRatio="xMaxYMax slice" viewBox="0 0 30 40"
             width="50" height="30">&Smile;</svg></g>
    </g>   
  </g>
</svg>

Example PreserveAspectRatio

View this example as SVG (SVG-enabled browsers only)

For the ‘preserveAspectRatio’ атрибут:

Animatable: yes.

7.9 Establishing a new viewport

At any point in an SVG drawing, you can establish a new viewport into which all contained graphics is drawn by including an ‘svg’ елемент inside SVG content. By establishing a new viewport, you also implicitly establish a new viewport coordinate system, a new user coordinate system, and, potentially, a new clipping path (see the definition of the ‘overflow’ властивість). Additionally, there is a new meaning for percentage units defined to be relative to the current viewport since a new viewport has been established (see Units).

The bounds of the new viewport are defined by the ‘x’, ‘y’, ‘width’ and ‘height’ атрибути on the елемент establishing the new viewport, such as an ‘svg’ елемент. Both the new viewport coordinate system and the new user coordinate system have their origins at (‘x’, ‘y’), where ‘x’ and ‘y’ represent the value of the corresponding атрибути on the елемент establishing the viewport. The orientation of the new viewport coordinate system and the new user coordinate system correspond to the orientation of the current user coordinate system for the елемент establishing the viewport. A single unit in the new viewport coordinate system and the new user coordinate system are the same size as a single unit in the current user coordinate system for the елемент establishing the viewport.

Here is an example:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="4in" height="3in" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>This SVG drawing embeds another one,
    thus establishing a new viewport
  </desc>
  <!-- The following statement establishing a new viewport
       and renders SVG drawing B into that viewport -->
  <svg x="25%" y="25%" width="50%" height="50%">
     <!-- drawing B goes here -->
  </svg>
</svg>

For an extensive example of creating new viewports, see Example PreserveAspectRatio.

The following елементи establish new viewports:

The ‘svg’ елемент
A ‘symbol’ елемент define new viewports whenever they are instanced by a ‘use’ елемент.
An ‘image’ елемент that references an SVG file will result in the establishment of a temporary new viewport since the referenced resource by definition will have an ‘svg’ елемент.
A ‘foreignObject’ елемент creates a new viewport for rendering the content that is within the елемент.

Whether a new viewport also establishes a new additional clipping path is determined by the value of the ‘overflow’ властивість on the елемент that establishes the new viewport. If a clipping path is created to correspond to the new viewport, the clipping path's geometry is determined by the value of the ‘clip’ властивість. Also, see Clip to viewport vs. clip to ‘viewBox’.

7.10 Units

All coordinates and lengths in SVG can be specified with or without a unit identifier.

When a coordinate or length value is a number without a unit identifier (e.g., "25"), then the given coordinate or length is assumed to be in user units (i.e., a value in the current user coordinate system). For example:

<text font-size="50">Text size is 50 user units</text>

Alternatively, a coordinate or length value can be expressed as a number followed by a unit identifier (e.g., "25cm" or "15em"). (Note that CSS defined властивості used in a CSS style sheet or the ‘style’ атрибут require units for non-zero lengths, see SVG's властивості стилю.) The list of unit identifiers in SVG matches the list of unit identifiers in CSS: em, ex, px, pt, pc, cm, mm and in. The <length> type can also have a percentage unit identifier. The following describes how the various unit identifiers are processed:

As in CSS, the em and ex unit identifiers are relative to the current font's font-size and x-height, respectively.
One px unit is defined to be equal to one user unit. Thus, a length of "5px" is the same as a length of "5".

Note that at initialization, a user unit in the the initial coordinate system is equivalenced to the parent environment's notion of a px unit. Thus, in the the initial coordinate system, because the user coordinate system aligns exactly with the parent's coordinate system, and because often the parent's coordinate system aligns with the device pixel grid, "5px" might actually map to 5 devices pixels. Якever, if there are any coordinate system transformation due to the use of ‘transform’ or ‘viewBox’ атрибути, because "5px" maps to 5 user units and because the coordinate system transformations have resulted in a revised user coordinate system, "5px" likely will not map to 5 device pixels. As a result, in most circumstances, "px" units will not map to the device pixel grid.
The other absolute unit identifiers from CSS (i.e., pt, pc, cm, mm, in) are all defined as an appropriate multiple of one px unit (which, according to the previous item, is defined to be equal to one user unit), based on what the SVG user agent determines is the size of a px unit (possibly passed from the parent processor or environment at initialization time). For example, suppose that the user agent can determine from its environment that "1px" corresponds to "0.2822222mm" (i.e., 90dpi). Then, for all processing of SVG content:
- "1pt" equals "1.25px" (and therefore 1.25 user units)
- "1pc" equals "15px" (and therefore 15 user units)
- "1mm" would be "3.543307px" (3.543307 user units)
- "1cm" equals "35.43307px" (and therefore 35.43307 user units)
- "1in" equals "90px" (and therefore 90 user units)

Note that use of px units or any other absolute unit identifiers can cause inconsistent visual results on different viewing environments since the size of "1px" may map to a different number of user units on different systems; thus, absolute units identifiers are only recommended for the ‘width’ and the ‘height’ on and situations where the content contains no transformations and it is desirable to specify values relative to the device pixel grid or to a particular real world unit size.

For percentage values that are defined to be relative to the size of viewport:

For any x-coordinate value or width value expressed as a percentage of the viewport, the value to use is the specified percentage of the actual-width in user units for the nearest containing viewport, where actual-width is the width dimension of the viewport елемент within the user coordinate system for the viewport елемент.
For any y-coordinate value or height value expressed as a percentage of the viewport, the value to use is the specified percentage of the actual-height in user units for the nearest containing viewport, where actual-height is the height dimension of the viewport елемент within the user coordinate system for the viewport елемент.
For any other length value expressed as a percentage of the viewport, the percentage is calculated as the specified percentage of sqrt((actual-width)**2 + (actual-height)**2))/sqrt(2).

Example Units below illustrates some of the processing rules for different types of units.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="400px" height="200px" viewBox="0 0 4000 2000"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example Units</title>
  <desc>Illustrates various units options</desc>

  <!-- Frame the picture -->
  <rect x="5" y="5" width="3990" height="1990" 
        fill="none" stroke="blue" stroke-width="10"/>

  <g fill="blue" stroke="red" font-family="Verdana" font-size="150">
    <!-- Absolute unit specifiers -->
    <g transform="translate(400,0)">
      <text x="-50" y="300" fill="black" stroke="none">Abs. units:</text>
      <rect x="0" y="400" width="4in" height="2in" stroke-width=".4in"/>
      <rect x="0" y="750" width="384" height="192" stroke-width="38.4"/>
      <g transform="scale(2)">
        <rect x="0" y="600" width="4in" height="2in" stroke-width=".4in"/>
      </g>
    </g>

    <!-- Relative unit specifiers -->
    <g transform="translate(1600,0)">
      <text x="-50" y="300" fill="black" stroke="none">Rel. units:</text>
      <rect x="0" y="400" width="2.5em" height="1.25em" stroke-width=".25em"/>
      <rect x="0" y="750" width="375" height="187.5" stroke-width="37.5"/>
      <g transform="scale(2)">
        <rect x="0" y="600" width="2.5em" height="1.25em" stroke-width=".25em"/>
      </g>
    </g>

    <!-- Percentages -->
    <g transform="translate(2800,0)">
      <text x="-50" y="300" fill="black" stroke="none">Percentages:</text>
      <rect x="0" y="400" width="10%" height="10%" stroke-width="1%"/>
      <rect x="0" y="750" width="400" height="200" stroke-width="31.62"/>
      <g transform="scale(2)">
        <rect x="0" y="600" width="10%" height="10%" stroke-width="1%"/>
      </g>
    </g>
  </g>
</svg>

Example Units

View this example as SVG (SVG-enabled browsers only)

The three rectangles on the left demonstrate the use of one of the absolute unit identifiers, the "in" unit (inch). The reference image above was generated on a 96dpi system (i.e., 1 inch = 96 pixels). Therefore, the topmost rectangle, which is specified in inches, is exactly the same size as the middle rectangle, which is specified in user units such that there are 96 user units for each corresponding inch in the topmost rectangle. (Note: on systems with different screen resolutions, the top and middle rectangles will likely be rendered at different sizes.) The bottom rectangle of the group illustrates what happens when values specified in inches are scaled.

The three rectangles in the middle demonstrate the use of one of the relative unit identifiers, the "em" unit. Because the ‘font-size’ властивість has been set to 150 on the outermost ‘g’ елемент, each "em" unit is equal to 150 user units. The topmost rectangle, which is specified in "em" units, is exactly the same size as the middle rectangle, which is specified in user units such that there are 150 user units for each corresponding "em" unit in the topmost rectangle. The bottom rectangle of the group illustrates what happens when values specified in "em" units are scaled.

The three rectangles on the right demonstrate the use of percentages. Note that the width and height of the viewport in the user coordinate system for the viewport елемент (in this case, the outermost svg елемент) are 4000 and 2000, respectively, because processing the ‘viewBox’ атрибут results in a transformed user coordinate system. The topmost rectangle, which is specified in percentage units, is exactly the same size as the middle rectangle, which is specified in equivalent user units. In particular, note that the ‘stroke-width’ властивість in the middle rectangle is set to 1% of the sqrt((actual-width)**2 + (actual-height)**2)) / sqrt(2), which in this case is .01*sqrt(4000*4000+2000*2000)/sqrt(2), or 31.62. The bottom rectangle of the group illustrates what happens when values specified in percentage units are scaled.

7.11 Object bounding box units

The following елементи offer the option of expressing coordinate values and lengths as fractions (and, in some cases, percentages) of the bounding box, by setting a specified атрибут to 'objectBoundingBox' on the given елемент:

Element	Attribute	Effect
‘linearGradient’	‘gradientUnits’	Indicates that the атрибути which specify the gradient vector (‘x1’, ‘y1’, ‘x2’, ‘y2’) represent fractions or percentages of the bounding box of the елемент to which the gradient is applied.
‘radialGradient’	‘gradientUnits’	Indicates that the атрибути which specify the center (‘cx’, ‘cy’), the radius (‘r’) and focus (‘fx’, ‘fy’) represent fractions or percentages of the bounding box of the елемент to which the gradient is applied.
‘pattern’	‘patternUnits’	Indicates that the атрибути which define how to tile the pattern (‘x’, ‘y’, ‘width’, ‘height’) are established using the bounding box of the елемент to which the pattern is applied.
‘pattern’	‘patternContentUnits’	Indicates that the user coordinate system for the contents of the pattern is established using the bounding box of the елемент to which the pattern is applied.
‘clipPath’	‘clipPathUnits’	Indicates that the user coordinate system for the contents of the ‘clipPath’ елемент is established using the bounding box of the елемент to which the clipping path is applied.
‘mask’	‘maskUnits’	Indicates that the атрибути which define the masking region (‘x’, ‘y’, ‘width’, ‘height’) is established using the bounding box of the елемент to which the mask is applied.
‘mask’	‘maskContentUnits’	Indicates that the user coordinate system for the contents of the ‘mask’ елемент are established using the bounding box of the елемент to which the mask is applied.
‘filter’	‘filterUnits’	Indicates that the атрибути which define the filter effects region (‘x’, ‘y’, ‘width’, ‘height’) represent fractions or percentages of the bounding box of the елемент to which the filter is applied.
‘filter’	‘primitiveUnits’	Indicates that the various length values within the filter primitives represent fractions or percentages of the bounding box of the елемент to which the filter is applied.

In the discussion that follows, the term applicable елемент is the елемент to which the given effect applies. For gradients and patterns, the applicable елемент is the graphics елемент which has its ‘fill’ or ‘stroke’ властивість referencing the given gradient or pattern. (See Inheritance of Painting Properties. For special rules concerning text елементи, see the discussion of object bounding box units and text елементи.) For clipping paths, masks and filters, the applicable елемент can be either a container елемент or a graphics елемент.

When keyword objectBoundingBox is used, then the effect is as if a supplemental transformation matrix were inserted into the list of nested transformation matrices to create a new user coordinate system.

First, the (minx,miny) and (maxx,maxy) coordinates are determined for the applicable елемент and all of its descendants. The values minx, miny, maxx and maxy are determined by computing the maximum extent of the shape of the елемент in X and Y with respect to the user coordinate system for the applicable елемент. The bounding box is the tightest fitting rectangle aligned with the axes of the applicable елемент's user coordinate system that entirely encloses the applicable елемент and its descendants. The bounding box is computed exclusive of any values for clipping, masking, filter effects, opacity and stroke-width. For curved shapes, the bounding box encloses all portions of the shape, not just end points. For ‘text’ елементи, for the purposes of the bounding box calculation, each glyph is treated as a separate graphics елемент. The calculations assume that all glyphs occupy the full glyph cell. For example, for horizontal text, the calculations assume that each glyph extends vertically to the full ascent and descent values for the font.

Then, coordinate (0,0) in the new user coordinate system is mapped to the (minx,miny) corner of the tight bounding box within the user coordinate system of the applicable елемент and coordinate (1,1) in the new user coordinate system is mapped to the (maxx,maxy) corner of the tight bounding box of the applicable елемент. In most situations, the following transformation matrix produces the correct effect:

[ (maxx-minx) 0 0 (maxy-miny) minx miny ]

When percentages are used with атрибути that define the gradient vector, the pattern tile, the filter region or the masking region, a percentage represents the same value as the corresponding decimal value (e.g., 50% means the same as 0.5). If percentages are used within the content of a ‘pattern’, ‘clipPath’, ‘mask’ or ‘filter’ елемент, these values are treated according to the processing rules for percentages as defined in Units.

Any numeric value can be specified for values expressed as a fraction or percentage of object bounding box units. In particular, fractions less are zero or greater than one and percentages less than 0% or greater than 100% can be specified.

Keyword objectBoundingBox should not be used when the geometry of the applicable елемент has no width or no height, such as the case of a horizontal or vertical line, even when the line has actual thickness when viewed due to having a non-zero stroke width since stroke width is ignored for bounding box calculations. When the geometry of the applicable елемент has no width or height and objectBoundingBox is specified, then the given effect (e.g., a gradient or a filter) will be ignored.

7.12 Intrinsic sizing властивості of the viewport of SVG content

SVG needs to specify how to calculate some intrinsic sizing властивості to enable inclusion within other languages. The intrinsic width and height of the viewport of SVG content must be determined from the ‘width’ and ‘height’ атрибути. If either of these are not specified, a value of '100%' must be assumed. Note: the ‘width’ and ‘height’ атрибути are not the same as the CSS width and height властивості. Specifically, percentage values do not provide an intrinsic width or height, and do not indicate a percentage of the containing block. Rather, once the viewport is established, they indicate the portion of the viewport that is actually covered by image data.

The intrinsic aspect ratio of the viewport of SVG content is necessary for example, when including SVG from an ‘object’ елемент in HTML styled with CSS. It is possible (indeed, common) for an SVG graphic to have an intrinsic aspect ratio but not to have an intrinsic width or height. The intrinsic aspect ratio must be calculated based upon the following rules:

The aspect ratio is calculated by dividing a width by a height.
If the ‘width’ and ‘height’ of the rootmost ‘svg’ елемент are both specified with unit identifiers (in, mm, cm, pt, pc, px, em, ex) or in user units, then the aspect ratio is calculated from the ‘width’ and ‘height’ атрибути after resolving both values to user units.
If either/both of the ‘width’ and ‘height’ of the rootmost ‘svg’ елемент are in percentage units (or omitted), the aspect ratio is calculated from the width and height values of the ‘viewBox’ specified for the current SVG document fragment. If the ‘viewBox’ is not correctly specified, or set to 'none', the intrinsic aspect ratio cannot be calculated and is considered unspecified.

Examples:

Example: Intrinsic Aspect Ratio 1

<svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny"
     width="10cm" height="5cm">
  ...
</svg>

In this example the intrinsic aspect ratio of the viewport is 2:1. The intrinsic width is 10cm and the intrinsic height is 5cm.

Example: Intrinsic Aspect Ratio 2

<svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny"
     width="100%" height="50%" viewBox="0 0 200 200">
  ...
</svg>

In this example the intrinsic aspect ratio of the rootmost viewport is 1:1. An aspect ratio calculation in this case allows embedding in an object within a containing block that is only constrained in one direction.

Example: Intrinsic Aspect Ratio 3

<svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny"
     width="10cm" viewBox="0 0 200 200">
  ...
</svg>

In this case the intrinsic aspect ratio is 1:1.

Example: Intrinsic Aspect Ratio 4

<svg xmlns="http://www.w3.org/2000/svg" version="1.2" baseProfile="tiny"
     width="75%" height="10cm" viewBox="0 0 200 200">
  ...
</svg>

In this example, the intrinsic aspect ratio is 1:1.

7.13 Geographic coordinate systems

In order to allow interoperability between SVG content generators and user agents dealing with maps encoded in SVG, the use of a common metadata definition for describing the coordinate system used to generate SVG documents is encouraged.

Such metadata must be added under the ‘metadata’ елемент of the topmost ‘svg’ елемент describing the map, consisting of an RDF description of the Coordinate Reference System definition used to generate the SVG map [RDF-PRIMER]. Note that the presence of this metadata does not affect the rendering of the SVG in any way; it merely provides added semantic value for applications that make use of combined maps.

The definition must be conformant to the XML grammar described in GML 3.2.1, an OpenGIS Standard for encoding common CRS типи даних in XML [GML]. In order to correctly map the 2-dimensional data used by SVG, the CRS must be of subtype ProjectedCRS or Geographic2dCRS. The first axis of the described CRS maps the SVG x-axis and the second axis maps the SVG y-axis.

The main purpose of such metadata is to indicate to the user agent that two or more SVG documents can be overlayed or merged into a single document. Obviously, if two maps reference the same Coordinate Reference System definition and have the same SVG ‘transform’ атрибут value then they can be overlayed without reprojecting the data. If the maps reference different Coordinate Reference Systems and/or have different SVG ‘transform’ атрибут values, then a specialized cartographic user agent may choose to transform the coordinate data to overlay the data. Якever, typical SVG user agents are not required to perform these types of transformations, or even recognize the metadata. It is described in this specification so that the connection between geographic coordinate systems and the SVG coordinate system is clear.

7.14 The ‘svg:transform’ атрибут

Attribute definition:

svg:transform = "<transform>" | "none"

<transform>: Specifies the affine transformation that has been applied to the map data. The syntax is identical to that described in The ‘transform’ атрибут section.
none: Specifies that no supplemental affine transformation has been applied to the map data. Using this value has the same meaning as specifying the identity matrix, which in turn is just the same as not specifying the ‘svg:transform’ the атрибут at all.

Animatable: no.

This атрибут describes an optional additional affine transformation that may have been applied during this mapping. This атрибут may be added to the OpenGIS ‘CoordinateReferenceSystem’ елемент. Note that, unlike the ‘transform’ атрибут, it does not indicate that a transformation is to be applied to the data within the file. Instead, it simply describes the transformation that was already applied to the data when being encoded in SVG.

There are three typical uses for the ‘svg:transform’ global атрибут. These are described below and used in the examples.

Most ProjectedCRS have the north direction represented by positive values of the second axis and conversely SVG has a y-down coordinate system. That's why, in order to follow the usual way to represent a map with the north at its top, it is recommended for that kind of ProjectedCRS to use the ‘svg:transform’ global атрибут with a 'scale(1, -1)' value as in the third example below.
Most Geographic2dCRS have the latitude as their first axis rather than the longitude, which means that the south-north axis would be represented by the x-axis in SVG instead of the usual y-axis. That's why, in order to follow the usual way to represent a map with the north at its top, it is recommended for that kind of Geographic2dCRS to use the ‘svg:transform’ global атрибут with a 'rotate(-90)' value as in the first example (while also adding the 'scale(1, -1)' as for ProjectedCRS).
In addition, when converting for profiles which place restrictions on precision of real number values, it may be useful to add an additional scaling factor to retain good precision for a specific area. When generating an SVG document from WGS84 geographic coordinates (EPGS 4326), we recommend the use of an additional 100 times scaling factor corresponding to an ‘svg:transform’ global атрибут with a 'rotate(-90) scale(100)' value (shown in the second example). Different scaling values may be required depending on the particular CRS.

Below is a simple example of the coordinate metadata, which describes the coordinate system used by the document via a URI.

<?xml version="1.0"?>
<svg xmlns="http://www.w3.org/2000/svg" version="1.1"
     width="100" height="100" viewBox="0 0 1000 1000">

  <desc>An example that references coordinate data.</desc>

  <metadata>
    <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
             xmlns:crs="http://www.ogc.org/crs"
             xmlns:svg="http://www.w3.org/2000/svg">
      <rdf:Description rdf:about="">
        <!-- The Coordinate Reference System is described
             through a URI. -->
        <crs:CoordinateReferenceSystem
            svg:transform="rotate(-90)"
            rdf:resource="http://www.example.org/srs/epsg.xml#4326"/>
      </rdf:Description>
    </rdf:RDF>
  </metadata>

  <!-- The actual map content -->
</svg>

The second example uses a well-known identifier to describe the coordinate system. Note that the coordinates used in the document have had the supplied transform applied.

<?xml version="1.0"?>
<svg xmlns="http://www.w3.org/2000/svg" version="1.1"
     width="100" height="100" viewBox="0 0 1000 1000">

  <desc>Example using a well known coordinate system.</desc>

  <metadata>
    <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
             xmlns:crs="http://www.ogc.org/crs"
             xmlns:svg="http://www.w3.org/2000/svg">
      <rdf:Description rdf:about="">
        <!-- In case of a well-known Coordinate Reference System
             an 'Identifier' is enough to describe the CRS -->
        <crs:CoordinateReferenceSystem svg:transform="rotate(-90) scale(100, 100)">
          <crs:Identifier>
            <crs:code>4326</crs:code>
            <crs:codeSpace>EPSG</crs:codeSpace>
            <crs:edition>5.2</crs:edition>
          </crs:Identifier>
        </crs:CoordinateReferenceSystem>
      </rdf:Description>
    </rdf:RDF>
  </metadata>

  <!-- The actual map content -->
</svg>

The third example defines the coordinate system completely within the SVG document.

<?xml version="1.0"?>
<svg xmlns="http://www.w3.org/2000/svg" version="1.1"
     width="100" height="100" viewBox="0 0 1000 1000">

  <desc>Coordinate metadata defined within the SVG document</desc>

  <metadata>
    <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
             xmlns:crs="http://www.ogc.org/crs"
             xmlns:svg="http://www.w3.org/2000/svg">
      <rdf:Description rdf:about="">
        <!-- For other CRS it should be entirely defined -->
        <crs:CoordinateReferenceSystem svg:transform="scale(1,-1)">
          <crs:NameSet>
            <crs:name>Mercator projection of WGS84</crs:name>
          </crs:NameSet>
          <crs:ProjectedCRS>
            <!-- The actual definition of the CRS -->
            <crs:CartesianCoordinateSystem>
              <crs:dimension>2</crs:dimension>
              <crs:CoordinateAxis>
                <crs:axisDirection>north</crs:axisDirection>
                <crs:AngularUnit>
                  <crs:Identifier>
                    <crs:code>9108</crs:code>
                    <crs:codeSpace>EPSG</crs:codeSpace>
                    <crs:edition>5.2</crs:edition>
                  </crs:Identifier>
                </crs:AngularUnit>
              </crs:CoordinateAxis>
              <crs:CoordinateAxis>
                <crs:axisDirection>east</crs:axisDirection>
                <crs:AngularUnit>
                  <crs:Identifier>
                    <crs:code>9108</crs:code>
                    <crs:codeSpace>EPSG</crs:codeSpace>
                    <crs:edition>5.2</crs:edition>
                  </crs:Identifier>
                </crs:AngularUnit>
              </crs:CoordinateAxis>
            </crs:CartesianCoordinateSystem>
            <crs:CoordinateReferenceSystem>
              <!-- the reference system of that projected system is
                         WGS84 which is EPSG 4326 in EPSG codeSpace -->
              <crs:NameSet>
                <crs:name>WGS 84</crs:name>
              </crs:NameSet>
              <crs:Identifier>
                <crs:code>4326</crs:code>
                <crs:codeSpace>EPSG</crs:codeSpace>
                <crs:edition>5.2</crs:edition>
              </crs:Identifier>
            </crs:CoordinateReferenceSystem>
            <crs:CoordinateTransformationDefinition>
              <crs:sourceDimensions>2</crs:sourceDimensions>
              <crs:targetDimensions>2</crs:targetDimensions>
              <crs:ParameterizedTransformation>
                <crs:TransformationMethod>
                  <!-- the projection is a Mercator projection which is
                        EPSG 9805 in EPSG codeSpace -->
                  <crs:NameSet>
                    <crs:name>Mercator</crs:name>
                  </crs:NameSet>
                  <crs:Identifier>
                    <crs:code>9805</crs:code>
                    <crs:codeSpace>EPSG</crs:codeSpace>
                    <crs:edition>5.2</crs:edition>
                  </crs:Identifier>
                  <crs:description>Mercator (2SP)</crs:description>
                </crs:TransformationMethod>
                <crs:Parameter>
                  <crs:NameSet>
                    <crs:name>Latitude of 1st standart parallel</crs:name>
                  </crs:NameSet>
                  <crs:Identifier>
                    <crs:code>8823</crs:code>
                    <crs:codeSpace>EPSG</crs:codeSpace>
                    <crs:edition>5.2</crs:edition>
                  </crs:Identifier>
                  <crs:value>0</crs:value>
                </crs:Parameter>
                <crs:Parameter>
                  <crs:NameSet>
                    <crs:name>Longitude of natural origin</crs:name>
                  </crs:NameSet>
                  <crs:Identifier>
                    <crs:code>8802</crs:code>
                    <crs:codeSpace>EPSG</crs:codeSpace>
                    <crs:edition>5.2</crs:edition>
                  </crs:Identifier>
                  <crs:value>0</crs:value>
                </crs:Parameter>
                <crs:Parameter>
                  <crs:NameSet>
                    <crs:name>False Easting</crs:name>
                  </crs:NameSet>
                  <crs:Identifier>
                    <crs:code>8806</crs:code>         
                    <crs:codeSpace>EPSG</crs:codeSpace>
                    <crs:edition>5.2</crs:edition>
                  </crs:Identifier>
                  <crs:value>0</crs:value>
                </crs:Parameter>
                <crs:Parameter>
                  <crs:NameSet>
                    <crs:name>False Northing</crs:name>
                  </crs:NameSet>
                  <crs:Identifier>
                    <crs:code>8807</crs:code>
                    <crs:codeSpace>EPSG</crs:codeSpace>
                    <crs:edition>5.2</crs:edition>
                  </crs:Identifier>
                  <crs:value>0</crs:value>
                </crs:Parameter>
              </crs:ParameterizedTransformation>
            </crs:CoordinateTransformationDefinition>
          </crs:ProjectedCRS>
        </crs:CoordinateReferenceSystem>
      </rdf:Description>
    </rdf:RDF>
  </metadata>

  <!-- the actual map content -->
</svg>

7.15 DOM interfaces

7.15.1 Інтерфейс SVGPoint

Many of the SVG DOM interfaces refer to objects of class SVGPoint. An SVGPoint is an (x, y) coordinate pair. When used in matrix operations, an SVGPoint is treated as a vector of the form:

[x]
[y]
[1]

If an SVGRect object is designated as read only, then attempting to assign to one of its атрибути will result in an exception being thrown.

interface SVGPoint {

  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);

  SVGPoint matrixTransform(in SVGMatrix matrix);
};

Attributes:

x (float)

The x coordinate.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised if the SVGPoint object is read only, or corresponds to a DOM атрибут that is read only.

y (float)

The y coordinate.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised if the SVGPoint object is read only, or corresponds to a DOM атрибут that is read only.

Operations:

SVGPoint matrixTransform(in SVGMatrix matrix)

Applies a 2x3 matrix transformation on this SVGPoint object and returns a new, transformed SVGPoint object:

newpoint = matrix * thispoint

Parameters

SVGMatrix matrix

The matrix which is to be applied to this SVGPoint object.

Returns

A new SVGPoint object.

7.15.2 Інтерфейс SVGPointList

This interface defines a list of SVGPoint objects.

SVGPointList has the same атрибути and methods as other SVGxxxList interfaces. Implementers may consider using a single base class to implement the various SVGxxxList interfaces.

interface SVGPointList {

  readonly атрибут unsigned long numberOfItems;

  void clear() raises(DOMException);
  SVGPoint initialize(in SVGPoint newItem) raises(DOMException);
  SVGPoint getItem(in unsigned long index) raises(DOMException);
  SVGPoint insertItemBefore(in SVGPoint newItem, in unsigned long index) raises(DOMException);
  SVGPoint replaceItem(in SVGPoint newItem, in unsigned long index) raises(DOMException);
  SVGPoint removeItem(in unsigned long index) raises(DOMException);
  SVGPoint appendItem(in SVGPoint newItem) raises(DOMException);
};

Attributes:

numberOfItems (readonly unsigned long): The number of items in the list.

Operations:

void clear()

Clears all existing current items from the list, with the result being an empty list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

SVGPoint initialize(in SVGPoint newItem)

Parameters

SVGPoint newItem

The item which should become the only member of the list.

Returns

The item being inserted into the list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

SVGPoint getItem(in unsigned long index)

Returns the specified item from the list. The returned item is the item itself and not a copy. Any changes made to the item are immediately reflected in the list.

Parameters

unsigned long index

The index of the item from the list which is to be returned. The first item is number 0.

Returns

The selected item.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGPoint insertItemBefore(in SVGPoint newItem, in unsigned long index)

Parameters

SVGPoint newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item before which the new item is to be inserted. The first item is number 0. If the index is equal to 0, then the new item is inserted at the front of the list. If the index is greater than or equal to numberOfItems, then the new item is appended to the end of the list.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

SVGPoint replaceItem(in SVGPoint newItem, in unsigned long index)

Parameters

SVGPoint newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item which is to be replaced. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGPoint removeItem(in unsigned long index)

Removes an existing item from the list.

Parameters

unsigned long index

The index of the item which is to be removed. The first item is number 0.

Returns

The removed item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGPoint appendItem(in SVGPoint newItem)

Parameters

SVGPoint newItem

The item which is to be inserted. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

7.15.3 Інтерфейс SVGMatrix

Many of SVG's graphics operations utilize 2x3 matrices of the form:

[a c e]
[b d f]

which, when expanded into a 3x3 matrix for the purposes of matrix arithmetic, become:

[a c e]
[b d f]
[0 0 1]

interface SVGMatrix {

  атрибут float a setraises(DOMException);
  атрибут float b setraises(DOMException);
  атрибут float c setraises(DOMException);
  атрибут float d setraises(DOMException);
  атрибут float e setraises(DOMException);
  атрибут float f setraises(DOMException);

  SVGMatrix multiply(in SVGMatrix secondMatrix);
  SVGMatrix inverse() raises(SVGException);
  SVGMatrix translate(in float x, in float y);
  SVGMatrix scale(in float scaleFactor);
  SVGMatrix scaleNonUniform(in float scaleFactorX, in float scaleFactorY);
  SVGMatrix rotate(in float angle);
  SVGMatrix rotateFromVector(in float x, in float y) raises(SVGException);
  SVGMatrix flipX();
  SVGMatrix flipY();
  SVGMatrix skewX(in float angle);
  SVGMatrix skewY(in float angle);
};

Attributes:

a (float)

The a component of the matrix.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

b (float)

The b component of the matrix.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

c (float)

The c component of the matrix.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

d (float)

The d component of the matrix.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

e (float)

The e component of the matrix.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

f (float)

The f component of the matrix.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

Operations:

SVGMatrix multiply(in SVGMatrix secondMatrix)

Performs matrix multiplication. This matrix is post-multiplied by another matrix, returning the resulting new matrix.

Parameters

SVGMatrix secondMatrix

The matrix which is post-multiplied to this matrix.

Returns

The resulting matrix.

SVGMatrix inverse()

Returns the inverse matrix.

Returns

The inverse matrix.

Exceptions

SVGException, code SVG_MATRIX_NOT_INVERTABLE: Raised if this matrix is not invertable.

SVGMatrix translate(in float x, in float y)

Post-multiplies a translation transformation on the current matrix and returns the resulting matrix.

Parameters

float x

The distance to translate along the x-axis.
float y

The distance to translate along the y-axis.

Returns

The resulting matrix.

SVGMatrix scale(in float scaleFactor)

Post-multiplies a uniform scale transformation on the current matrix and returns the resulting matrix.

Parameters

float scaleFactor

Scale factor in both X and Y.

Returns

The resulting matrix.

SVGMatrix scaleNonUniform(in float scaleFactorX, in float scaleFactorY)

Post-multiplies a non-uniform scale transformation on the current matrix and returns the resulting matrix.

Parameters

float scaleFactorX

Scale factor in X.
float scaleFactorY

Scale factor in Y.

Returns

The resulting matrix.

SVGMatrix rotate(in float angle)

Post-multiplies a rotation transformation on the current matrix and returns the resulting matrix.

Parameters

float angle

Rotation angle.

Returns

The resulting matrix.

SVGMatrix rotateFromVector(in float x, in float y)

Post-multiplies a rotation transformation on the current matrix and returns the resulting matrix. The rotation angle is determined by taking (+/-) atan(y/x). The direction of the vector (x, y) determines whether the positive or negative angle value is used.

Parameters

float x

The X coordinate of the vector (x,y). Must not be zero.
float y

The Y coordinate of the vector (x,y). Must not be zero.

Returns

The resulting matrix.

Exceptions

SVGException, code SVG_INVALID_VALUE_ERR: Raised if one of the parameters has an invalid value.

SVGMatrix flipX()

Post-multiplies the transformation [-1 0 0 1 0 0] and returns the resulting matrix.

Returns: The resulting matrix.

SVGMatrix flipY()

Post-multiplies the transformation [1 0 0 -1 0 0] and returns the resulting matrix.

Returns: The resulting matrix.

SVGMatrix skewX(in float angle)

Post-multiplies a skewX transformation on the current matrix and returns the resulting matrix.

Parameters

float angle

Skew angle.

Returns

The resulting matrix.

SVGMatrix skewY(in float angle)

Post-multiplies a skewY transformation on the current matrix and returns the resulting matrix.

Parameters

float angle

Skew angle.

Returns

The resulting matrix.

7.15.4 Інтерфейс SVGTransform

SVGTransform is the interface for one of the component transformations within an SVGTransformList; thus, an SVGTransform object corresponds to a single component (e.g., 'scale(…)' or 'matrix(…)') within a ‘transform’ атрибут specification.

interface SVGTransform {

  // Transform Types
  const unsigned short SVG_TRANSFORM_UNKNOWN = 0;
  const unsigned short SVG_TRANSFORM_MATRIX = 1;
  const unsigned short SVG_TRANSFORM_TRANSLATE = 2;
  const unsigned short SVG_TRANSFORM_SCALE = 3;
  const unsigned short SVG_TRANSFORM_ROTATE = 4;
  const unsigned short SVG_TRANSFORM_SKEWX = 5;
  const unsigned short SVG_TRANSFORM_SKEWY = 6;

  readonly атрибут unsigned short type;
  readonly атрибут SVGMatrix matrix;
  readonly атрибут float angle;

  void setMatrix(in SVGMatrix matrix) raises(DOMException);
  void setTranslate(in float tx, in float ty) raises(DOMException);
  void setScale(in float sx, in float sy) raises(DOMException);
  void setRotate(in float angle, in float cx, in float cy) raises(DOMException);
  void setSkewX(in float angle) raises(DOMException);
  void setSkewY(in float angle) raises(DOMException);
};

Constants in group “Transform Types”:

SVG_TRANSFORM_UNKNOWN (unsigned short): The unit type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_TRANSFORM_MATRIX (unsigned short): A 'matrix(…)' transformation.
SVG_TRANSFORM_TRANSLATE (unsigned short): A 'translate(…)' transformation.
SVG_TRANSFORM_SCALE (unsigned short): A 'scale(…)' transformation.
SVG_TRANSFORM_ROTATE (unsigned short): A 'rotate(…)' transformation.
SVG_TRANSFORM_SKEWX (unsigned short): A 'skewX(…)' transformation.
SVG_TRANSFORM_SKEWY (unsigned short): A 'skewY(…)' transformation.

Attributes:

type (readonly unsigned short)

The type of the value as specified by one of the SVG_TRANSFORM_* constants defined on this interface.

matrix (readonly SVGMatrix)

The matrix that represents this transformation. The matrix object is live, meaning that any changes made to the SVGTransform object are immediately reflected in the matrix object and vice versa. In case the matrix object is changed directly (i.e., without using the methods on the SVGTransform interface itself) then the type of the SVGTransform changes to SVG_TRANSFORM_MATRIX.

For SVG_TRANSFORM_MATRIX, the matrix contains the a, b, c, d, e, f values supplied by the user.
For SVG_TRANSFORM_TRANSLATE, e and f represent the translation amounts (a=1, b=0, c=0 and d=1).
For SVG_TRANSFORM_SCALE, a and d represent the scale amounts (b=0, c=0, e=0 and f=0).
For SVG_TRANSFORM_SKEWX and SVG_TRANSFORM_SKEWY, a, b, c and d represent the matrix which will result in the given skew (e=0 and f=0).
For SVG_TRANSFORM_ROTATE, a, b, c, d, e and f together represent the matrix which will result in the given rotation. When the rotation is around the center point (0, 0), e and f will be zero.

angle (readonly float)

A convenience атрибут for SVG_TRANSFORM_ROTATE, SVG_TRANSFORM_SKEWX and SVG_TRANSFORM_SKEWY. It holds the angle that was specified.

For SVG_TRANSFORM_MATRIX, SVG_TRANSFORM_TRANSLATE and SVG_TRANSFORM_SCALE, angle will be zero.

Operations:

void setMatrix(in SVGMatrix matrix)

Sets the transform type to SVG_TRANSFORM_MATRIX, with parameter matrix defining the new transformation. The values from the parameter matrix are copied, the matrix parameter does not replace SVGTransform::matrix.

Parameters

SVGMatrix matrix

The new matrix for the transformation.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

void setTranslate(in float tx, in float ty)

Sets the transform type to SVG_TRANSFORM_TRANSLATE, with parameters tx and ty defining the translation amounts.

Parameters

float tx

The translation amount in X.
float ty

The translation amount in Y.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

void setScale(in float sx, in float sy)

Sets the transform type to SVG_TRANSFORM_SCALE, with parameters sx and sy defining the scale amounts.

Parameters

float sx

The scale amount in X.
float sy

The scale amount in Y.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

void setRotate(in float angle, in float cx, in float cy)

Sets the transform type to SVG_TRANSFORM_ROTATE, with parameter angle defining the rotation angle and parameters cx and cy defining the optional center of rotation.

Parameters

float angle

The rotation angle.
float cx

The x coordinate of center of rotation.
float cy

The y coordinate of center of rotation.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

void setSkewX(in float angle)

Sets the transform type to SVG_TRANSFORM_SKEWX, with parameter angle defining the amount of skew.

Parameters

float angle

The skew angle.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

void setSkewY(in float angle)

Sets the transform type to SVG_TRANSFORM_SKEWY, with parameter angle defining the amount of skew.

Parameters

float angle

The skew angle.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

7.15.5 Інтерфейс SVGTransformList

This interface defines a list of SVGTransform objects.

The SVGTransformList and SVGTransform interfaces correspond to the various атрибути which specify a set of transformations, such as the ‘transform’ атрибут which is available for many of SVG's елементи.

SVGTransformList has the same атрибути and methods as other SVGxxxList interfaces. Implementers may consider using a single base class to implement the various SVGxxxList interfaces.

An SVGTransformList object can be designated as read only, which means that attempts to modify the object will result in an exception being thrown, as described below.

interface SVGTransformList {

  readonly атрибут unsigned long numberOfItems;

  void clear() raises(DOMException);
  SVGTransform initialize(in SVGTransform newItem) raises(DOMException);
  SVGTransform getItem(in unsigned long index) raises(DOMException);
  SVGTransform insertItemBefore(in SVGTransform newItem, in unsigned long index) raises(DOMException);
  SVGTransform replaceItem(in SVGTransform newItem, in unsigned long index) raises(DOMException);
  SVGTransform removeItem(in unsigned long index) raises(DOMException);
  SVGTransform appendItem(in SVGTransform newItem) raises(DOMException);
  SVGTransform createSVGTransformFromMatrix(in SVGMatrix matrix);
  SVGTransform consolidate() raises(DOMException);
};

Attributes:

numberOfItems (readonly unsigned long): The number of items in the list.

Operations:

void clear()

Clears all existing current items from the list, with the result being an empty list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGTransform initialize(in SVGTransform newItem)

Parameters

SVGTransform newItem

The item which should become the only member of the list.

Returns

The item being inserted into the list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGTransform getItem(in unsigned long index)

Returns the specified item from the list. The returned item is the item itself and not a copy. Any changes made to the item are immediately reflected in the list.

Parameters

unsigned long index

The index of the item from the list which is to be returned. The first item is number 0.

Returns

The selected item.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGTransform insertItemBefore(in SVGTransform newItem, in unsigned long index)

Parameters

SVGTransform newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item before which the new item is to be inserted. The first item is number 0. If the index is equal to 0, then the new item is inserted at the front of the list. If the index is greater than or equal to numberOfItems, then the new item is appended to the end of the list.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGTransform replaceItem(in SVGTransform newItem, in unsigned long index)

Parameters

SVGTransform newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item which is to be replaced. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGTransform removeItem(in unsigned long index)

Removes an existing item from the list.

Parameters

unsigned long index

The index of the item which is to be removed. The first item is number 0.

Returns

The removed item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGTransform appendItem(in SVGTransform newItem)

Parameters

SVGTransform newItem

The item which is to be inserted. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

SVGTransform createSVGTransformFromMatrix(in SVGMatrix matrix)

Creates an SVGTransform object which is initialized to transform of type SVG_TRANSFORM_MATRIX and whose values are the given matrix. The values from the parameter matrix are copied, the matrix parameter is not adopted as SVGTransform::matrix.

Parameters

SVGMatrix matrix

The matrix which defines the transformation.

Returns

The returned SVGTransform object.

SVGTransform consolidate()

Consolidates the list of separate SVGTransform objects by multiplying the equivalent transformation matrices together to result in a list consisting of a single SVGTransform object of type SVG_TRANSFORM_MATRIX. The consolidation operation creates new SVGTransform object as the first and only item in the list. The returned item is the item itself and not a copy. Any changes made to the item are immediately reflected in the list.

Returns

The resulting SVGTransform object which becomes single item in the list. If the list was empty, then a value of null is returned.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list corresponds to a read only атрибут or when the object itself is read only.

7.15.6 Інтерфейс SVGAnimatedTransformList

Used for the various атрибути which specify a set of transformations, such as the ‘transform’ атрибут which is available for many of SVG's елементи, and which can be animated.

interface SVGAnimatedTransformList {
  readonly атрибут SVGTransformList baseVal;
  readonly атрибут SVGTransformList animVal;
};

Attributes:

baseVal (readonly SVGTransformList): The base value of the given атрибут before applying any animations.
animVal (readonly SVGTransformList): A read only SVGTransformList representing the current animated value of the given атрибут. If the given атрибут is not currently being animated, then the SVGTransformList will have the same contents as baseVal. The object referenced by animVal will always be distinct from the one referenced by baseVal, even when the атрибут is not animated.

7.15.7 Інтерфейс SVGPreserveAspectRatio

The SVGPreserveAspectRatio interface corresponds to the ‘preserveAspectRatio’ атрибут, which is available for some of SVG's елементи.

An SVGPreserveAspectRatio object can be designated as read only, which means that attempts to modify the object will result in an exception being thrown, as described below.

interface SVGPreserveAspectRatio {

  // Alignment Types
  const unsigned short SVG_PRESERVEASPECTRATIO_UNKNOWN = 0;
  const unsigned short SVG_PRESERVEASPECTRATIO_NONE = 1;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMINYMIN = 2;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMIDYMIN = 3;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMAXYMIN = 4;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMINYMID = 5;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMIDYMID = 6;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMAXYMID = 7;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMINYMAX = 8;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMIDYMAX = 9;
  const unsigned short SVG_PRESERVEASPECTRATIO_XMAXYMAX = 10;

  // Meet-or-slice Types
  const unsigned short SVG_MEETORSLICE_UNKNOWN = 0;
  const unsigned short SVG_MEETORSLICE_MEET = 1;
  const unsigned short SVG_MEETORSLICE_SLICE = 2;

  атрибут unsigned short align setraises(DOMException);
  атрибут unsigned short meetOrSlice setraises(DOMException);
};

Constants in group “Alignment Types”:

SVG_PRESERVEASPECTRATIO_UNKNOWN (unsigned short): The enumeration was set to a value that is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_PRESERVEASPECTRATIO_NONE (unsigned short): Corresponds to value 'none' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMINYMIN (unsigned short): Corresponds to value 'xMinYMin' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMIDYMIN (unsigned short): Corresponds to value 'xMidYMin' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMAXYMIN (unsigned short): Corresponds to value 'xMaxYMin' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMINYMID (unsigned short): Corresponds to value 'XMinYMid' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMIDYMID (unsigned short): Corresponds to value 'xMidYMid' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMAXYMID (unsigned short): Corresponds to value 'xMaxYMid' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMINYMAX (unsigned short): Corresponds to value 'xMinYMax' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMIDYMAX (unsigned short): Corresponds to value 'xMidYMax' for атрибут ‘preserveAspectRatio’.
SVG_PRESERVEASPECTRATIO_XMAXYMAX (unsigned short): Corresponds to value 'xMaxYMax' for атрибут ‘preserveAspectRatio’.

Constants in group “Meet-or-slice Types”:

SVG_MEETORSLICE_UNKNOWN (unsigned short): The enumeration was set to a value that is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_MEETORSLICE_MEET (unsigned short): Corresponds to value 'meet' for атрибут ‘preserveAspectRatio’.
SVG_MEETORSLICE_SLICE (unsigned short): Corresponds to value 'slice' for атрибут ‘preserveAspectRatio’.

Attributes:

align (unsigned short)

The type of the alignment value as specified by one of the SVG_PRESERVEASPECTRATIO_* constants defined on this interface.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the object corresponds to a read only атрибут or when the object itself is read only.

meetOrSlice (unsigned short)

The type of the meet-or-slice value as specified by one of the SVG_MEETORSLICE_* constants defined on this interface.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the object corresponds to a read only атрибут or when the object itself is read only.

7.15.8 Інтерфейс SVGAnimatedPreserveAspectRatio

Used for атрибути of type SVGPreserveAspectRatio which can be animated.

interface SVGAnimatedPreserveAspectRatio {
  readonly атрибут SVGPreserveAspectRatio baseVal;
  readonly атрибут SVGPreserveAspectRatio animVal;
};

Attributes:

baseVal (readonly SVGPreserveAspectRatio): The base value of the given атрибут before applying any animations.
animVal (readonly SVGPreserveAspectRatio): A read only SVGPreserveAspectRatio representing the current animated value of the given атрибут. If the given атрибут is not currently being animated, then the SVGPreserveAspectRatio will have the same contents as baseVal. The object referenced by animVal will always be distinct from the one referenced by baseVal, even when the атрибут is not animated.

8 Paths

8.1 Вступ
8.2 The ‘path’ елемент
8.3 Path data
8.4 Distance along a path
8.5 DOM interfaces

8.1 Вступ

Paths represent the outline of a shape which can be filled, stroked, used as a clipping path, or any combination of the three. (See Filling, Stroking and Paint Servers and Clipping, Masking and Compositing.)

A path is described using the concept of a current point. In an analogy with drawing on paper, the current point can be thought of as the location of the pen. The position of the pen can be changed, and the outline of a shape (open or closed) can be traced by dragging the pen in either straight lines or curves.

Paths represent the geometry of the outline of an object, defined in terms of moveto (set a new current point), lineto (draw a straight line), curveto (draw a curve using a cubic Bézier), arc (elliptical or circular arc) and closepath (close the current shape by drawing a line to the last moveto) елементи. Compound paths (i.e., a path with multiple subpaths) are possible to allow effects such as "donut holes" in objects.

This chapter describes the syntax, behavior and DOM interfaces for SVG paths. Various implementation notes for SVG paths can be found in ‘path’ елемент implementation notes and Elliptical arc implementation notes.

A path is defined in SVG using the ‘path’ елемент.

8.2 The ‘path’ елемент

‘path’

Categories:

Graphics елемент, shape елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘d’
‘pathLength’

DOM Інтерфейсs:

SVGPathElement

Attribute definitions:

d = "path data": The definition of the outline of a shape. See Path data.
Animatable: yes. Path data animation is only possible when each path data specification within an animation specification has exactly the same list of path data commands as the ‘d’ атрибут. If an animation is specified and the list of path data commands is not the same, then the animation specification is in error (see Error Processing). The animation engine interpolates each parameter to each path data command separately based on the атрибути to the given animation елемент. Flags and booleans are interpolated as fractions between zero and one, with any non-zero value considered to be a value of one/true.
pathLength = "<number>": The author's computation of the total length of the path, in user units. This value is used to calibrate the user agent's own distance-along-a-path calculations with that of the author. The user agent will scale all distance-along-a-path computations by the ratio of ‘pathLength’ to the user agent's own computed value for total path length. ‘pathLength’ potentially affects calculations for text on a path, motion animation and various stroke operations.
A negative value is an error (see Error processing).
Animatable: yes.

8.3 Path data

8.3.1 General information about path data

A path is defined by including a ‘path’ елемент which contains a d="(path data)" атрибут, where the ‘d’ атрибут contains the moveto, line, curve (both cubic and quadratic Béziers), arc and closepath instructions.

Example triangle01 specifies a path in the shape of a triangle. (The M indicates a moveto, the Ls indicate linetos, and the z indicates a closepath).

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="4cm" height="4cm" viewBox="0 0 400 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example triangle01- simple example of a 'path'</title>
  <desc>A path that draws a triangle</desc>
  <rect x="1" y="1" width="398" height="398"
        fill="none" stroke="blue" />
  <path d="M 100 100 L 300 100 L 200 300 z"
        fill="red" stroke="blue" stroke-width="3" />
</svg>

Example triangle01

View this example as SVG (SVG-enabled browsers only)

Path data can contain newline characters and thus can be broken up into multiple lines to improve readability. Because of line length limitations with certain related tools, it is recommended that SVG generators split long path data strings across multiple lines, with each line not exceeding 255 characters. Also note that newline characters are only allowed at certain places within path data.

The syntax of path data is concise in order to allow for minimal file size and efficient downloads, since many SVG files will be dominated by their path data. Some of the ways that SVG attempts to minimize the size of path data are as follows:

All instructions are expressed as one character (e.g., a moveto is expressed as an M).
Superfluous white space and separators such as commas can be eliminated (e.g., "M 100 100 L 200 200" contains unnecessary spaces and could be expressed more compactly as "M100 100L200 200").
The command letter can be eliminated on subsequent commands if the same command is used multiple times in a row (e.g., you can drop the second "L" in "M 100 200 L 200 100 L -100 -200" and use "M 100 200 L 200 100 -100 -200" instead).
Relative versions of all commands are available (uppercase means absolute coordinates, lowercase means relative coordinates).
Alternate forms of lineto are available to optimize the special cases of horizontal and vertical lines (absolute and relative).
Alternate forms of curve are available to optimize the special cases where some of the control points on the current segment can be determined automatically from the control points on the previous segment.

The path data syntax is a prefix notation (i.e., commands followed by parameters). The only allowable decimal point is a Unicode U+0046 FULL STOP (".") character (also referred to in Unicode as PERIOD, dot and decimal point) and no other delimiter characters are allowed [UNICODE]. (For example, the following is an invalid numeric value in a path data stream: "13,000.56". Instead, say: "13000.56".)

For the relative versions of the commands, all coordinate values are relative to the current point at the start of the command.

In the tables below, the following notation is used:

(): grouping of parameters
+: 1 or more of the given parameter(s) is required

The following sections list the commands.

8.3.2 The "moveto" commands

The "moveto" commands (M or m) establish a new current point. The effect is as if the "pen" were lifted and moved to a new location. A path data segment (if there is one) must begin with a "moveto" command. Subsequent "moveto" commands (i.e., when the "moveto" is not the first command) represent the start of a new subpath:

Command	Name	Parameters	Description
M (absolute) m (relative)	moveto	(x y)+	Start a new sub-path at the given (x,y) coordinate. M (uppercase) indicates that absolute coordinates will follow; m (lowercase) indicates that relative coordinates will follow. If a moveto is followed by multiple pairs of coordinates, the subsequent pairs are treated as implicit lineto commands. Hence, implicit lineto commands will be relative if the moveto is relative, and absolute if the moveto is absolute. If a relative moveto (m) appears as the first елемент of the path, then it is treated as a pair of absolute coordinates. In this case, subsequent pairs of coordinates are treated as relative even though the initial moveto is interpreted as an absolute moveto.

8.3.3 The "closepath" command

The "closepath" (Z or z) ends the current subpath and causes an automatic straight line to be drawn from the current point to the initial point of the current subpath. If a "closepath" is followed immediately by a "moveto", then the "moveto" identifies the start point of the next subpath. If a "closepath" is followed immediately by any other command, then the next subpath starts at the same initial point as the current subpath.

When a subpath ends in a "closepath," it differs in behavior from what happens when "manually" closing a subpath via a "lineto" command in how ‘stroke-linejoin’ and ‘stroke-linecap’ are implemented. With "closepath", the end of the final segment of the subpath is "joined" with the start of the initial segment of the subpath using the current value of ‘stroke-linejoin’. If you instead "manually" close the subpath via a "lineto" command, the start of the first segment and the end of the last segment are not joined but instead are each capped using the current value of ‘stroke-linecap’. At the end of the command, the new current point is set to the initial point of the current subpath.

Command	Name	Parameters	Description
Z or z	closepath	(none)	Close the current subpath by drawing a straight line from the current point to current subpath's initial point. Since the Z and z commands take no parameters, they have an identical effect.

8.3.4 The "lineto" commands

The various "lineto" commands draw straight lines from the current point to a new point:

Command	Name	Parameters	Description
L (absolute) l (relative)	lineto	(x y)+	Draw a line from the current point to the given (x,y) coordinate which becomes the new current point. L (uppercase) indicates that absolute coordinates will follow; l (lowercase) indicates that relative coordinates will follow. A number of coordinates pairs may be specified to draw a polyline. At the end of the command, the new current point is set to the final set of coordinates provided.
H (absolute) h (relative)	horizontal lineto	x+	Draws a horizontal line from the current point (cpx, cpy) to (x, cpy). H (uppercase) indicates that absolute coordinates will follow; h (lowercase) indicates that relative coordinates will follow. Multiple x values can be provided (although usually this doesn't make sense). At the end of the command, the new current point becomes (x, cpy) for the final value of x.
V (absolute) v (relative)	vertical lineto	y+	Draws a vertical line from the current point (cpx, cpy) to (cpx, y). V (uppercase) indicates that absolute coordinates will follow; v (lowercase) indicates that relative coordinates will follow. Multiple y values can be provided (although usually this doesn't make sense). At the end of the command, the new current point becomes (cpx, y) for the final value of y.

8.3.5 The curve commands

These three групи of commands draw curves:

Cubic Bézier commands (C, c, S and s). A cubic Bézier segment is defined by a start point, an end point, and two control points.
Quadratic Bézier commands (Q, q, T and t). A quadratic Bézier segment is defined by a start point, an end point, and one control point.
Elliptical arc commands (A and a). An elliptical arc segment draws a segment of an ellipse.

8.3.6 The cubic Bézier curve commands

The cubic Bézier commands are as follows:

Command	Name	Parameters	Description
C (absolute) c (relative)	curveto	(x1 y1 x2 y2 x y)+	Draws a cubic Bézier curve from the current point to (x,y) using (x1,y1) as the control point at the beginning of the curve and (x2,y2) as the control point at the end of the curve. C (uppercase) indicates that absolute coordinates will follow; c (lowercase) indicates that relative coordinates will follow. Multiple sets of coordinates may be specified to draw a polybézier. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybézier.
S (absolute) s (relative)	shorthand/smooth curveto	(x2 y2 x y)+	Draws a cubic Bézier curve from the current point to (x,y). The first control point is assumed to be the reflection of the second control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not an C, c, S or s, assume the first control point is coincident with the current point.) (x2,y2) is the second control point (i.e., the control point at the end of the curve). S (uppercase) indicates that absolute coordinates will follow; s (lowercase) indicates that relative coordinates will follow. Multiple sets of coordinates may be specified to draw a polybézier. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybézier.

Example cubic01 shows some simple uses of cubic Bézier commands within a path. The example uses an internal CSS style sheet to assign властивості стилю. Note that the control point for the "S" command is computed automatically as the reflection of the control point for the previous "C" command relative to the start point of the "S" command.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="5cm" height="4cm" viewBox="0 0 500 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example cubic01- cubic Bézier commands in path data</title>
  <desc>Picture showing a simple example of path data
        using both a "C" and an "S" command,
        along with annotations showing the control points
        and end points</desc>
  <style type="text/css"><![CDATA[
    .Border { fill:none; stroke:blue; stroke-width:1 }
    .Connect { fill:none; stroke:#888888; stroke-width:2 }
    .SamplePath { fill:none; stroke:red; stroke-width:5 }
    .EndPoint { fill:none; stroke:#888888; stroke-width:2 }
    .CtlPoint { fill:#888888; stroke:none }
    .AutoCtlPoint { fill:none; stroke:blue; stroke-width:4 }
    .Label { font-size:22; font-family:Verdana }
  ]]></style>

  <rect class="Border" x="1" y="1" width="498" height="398" />

  <polyline class="Connect" points="100,200 100,100" />
  <polyline class="Connect" points="250,100 250,200" />
  <polyline class="Connect" points="250,200 250,300" />
  <polyline class="Connect" points="400,300 400,200" />
  <path class="SamplePath" d="M100,200 C100,100 250,100 250,200
                                       S400,300 400,200" />
  <circle class="EndPoint" cx="100" cy="200" r="10" />
  <circle class="EndPoint" cx="250" cy="200" r="10" />
  <circle class="EndPoint" cx="400" cy="200" r="10" />
  <circle class="CtlPoint" cx="100" cy="100" r="10" />
  <circle class="CtlPoint" cx="250" cy="100" r="10" />
  <circle class="CtlPoint" cx="400" cy="300" r="10" />
  <circle class="AutoCtlPoint" cx="250" cy="300" r="9" />
  <text class="Label" x="25" y="70">M100,200 C100,100 250,100 250,200</text>
  <text class="Label" x="325" y="350"
        style="text-anchor:middle">S400,300 400,200</text>
</svg>

Example cubic01

View this example as SVG (SVG-enabled browsers only)

The following picture shows some how cubic Bézier curves change their shape depending on the position of the control points. The first five examples illustrate a single cubic Bézier path segment. The example at the lower right shows a "C" command followed by an "S" command.

Example cubic02 - cubic Bézier commands in path data

View this example as SVG (SVG-enabled browsers only)

8.3.7 The quadratic Bézier curve commands

The quadratic Bézier commands are as follows:

Command	Name	Parameters	Description
Q (absolute) q (relative)	quadratic Bézier curveto	(x1 y1 x y)+	Draws a quadratic Bézier curve from the current point to (x,y) using (x1,y1) as the control point. Q (uppercase) indicates that absolute coordinates will follow; q (lowercase) indicates that relative coordinates will follow. Multiple sets of coordinates may be specified to draw a polybézier. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybézier.
T (absolute) t (relative)	Shorthand/smooth quadratic Bézier curveto	(x y)+	Draws a quadratic Bézier curve from the current point to (x,y). The control point is assumed to be the reflection of the control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not a Q, q, T or t, assume the control point is coincident with the current point.) T (uppercase) indicates that absolute coordinates will follow; t (lowercase) indicates that relative coordinates will follow. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybézier.

Example quad01 shows some simple uses of quadratic Bézier commands within a path. Note that the control point for the "T" command is computed automatically as the reflection of the control point for the previous "Q" command relative to the start point of the "T" command.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="6cm" viewBox="0 0 1200 600"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example quad01 - quadratic Bézier commands in path data</title>
  <desc>Picture showing a "Q" a "T" command,
        along with annotations showing the control points
        and end points</desc>
  <rect x="1" y="1" width="1198" height="598"
        fill="none" stroke="blue" stroke-width="1" />

  <path d="M200,300 Q400,50 600,300 T1000,300"
        fill="none" stroke="red" stroke-width="5"  />
  <!-- End points -->
  <g fill="black" >
    <circle cx="200" cy="300" r="10"/>
    <circle cx="600" cy="300" r="10"/>
    <circle cx="1000" cy="300" r="10"/>
  </g>
  <!-- Control points and lines from end points to control points -->
  <g fill="#888888" >
    <circle cx="400" cy="50" r="10"/>
    <circle cx="800" cy="550" r="10"/>
  </g>
  <path d="M200,300 L400,50 L600,300 
           L800,550 L1000,300"
        fill="none" stroke="#888888" stroke-width="2" />
</svg>

Example quad01

View this example as SVG (SVG-enabled browsers only)

8.3.8 The elliptical arc curve commands

The elliptical arc commands are as follows:

Command	Name	Parameters	Description
A (absolute) a (relative)	elliptical arc	(rx ry x-axis-rotation large-arc-flag sweep-flag x y)+	Draws an elliptical arc from the current point to (x, y). The size and orientation of the ellipse are defined by two radii (rx, ry) and an x-axis-rotation, which indicates how the ellipse as a whole is rotated relative to the current coordinate system. The center (cx, cy) of the ellipse is calculated automatically to satisfy the constraints imposed by the other parameters. large-arc-flag and sweep-flag contribute to the automatic calculations and help determine how the arc is drawn.

Example arcs01 shows some simple uses of arc commands within a path.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="5.25cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example arcs01 - arc commands in path data</title>
  <desc>Picture of a pie chart with two pie wedges and
        a picture of a line with arc blips</desc>
  <rect x="1" y="1" width="1198" height="398"
        fill="none" stroke="blue" stroke-width="1" />

  <path d="M300,200 h-150 a150,150 0 1,0 150,-150 z"
        fill="red" stroke="blue" stroke-width="5" />
  <path d="M275,175 v-150 a150,150 0 0,0 -150,150 z"
        fill="yellow" stroke="blue" stroke-width="5" />

  <path d="M600,350 l 50,-25 
           a25,25 -30 0,1 50,-25 l 50,-25 
           a25,50 -30 0,1 50,-25 l 50,-25 
           a25,75 -30 0,1 50,-25 l 50,-25 
           a25,100 -30 0,1 50,-25 l 50,-25"
        fill="none" stroke="red" stroke-width="5"  />
</svg>

Example arcs01

View this example as SVG (SVG-enabled browsers only)

The elliptical arc command draws a section of an ellipse which meets the following constraints:

the arc starts at the current point
the arc ends at point (x, y)
the ellipse has the two radii (rx, ry)
the x-axis of the ellipse is rotated by x-axis-rotation relative to the x-axis of the current coordinate system.

For most situations, there are actually four different arcs (two different ellipses, each with two different arc sweeps) that satisfy these constraints. large-arc-flag and sweep-flag indicate which one of the four arcs are drawn, as follows:

Of the four candidate arc sweeps, two will represent an arc sweep of greater than or equal to 180 degrees (the "large-arc"), and two will represent an arc sweep of less than or equal to 180 degrees (the "small-arc"). If large-arc-flag is '1', then one of the two larger arc sweeps will be chosen; otherwise, if large-arc-flag is '0', one of the smaller arc sweeps will be chosen,
If sweep-flag is '1', then the arc will be drawn in a "positive-angle" direction (i.e., the ellipse formula x=cx+rx*cos(theta) and y=cy+ry*sin(theta) is evaluated such that theta starts at an angle corresponding to the current point and increases positively until the arc reaches (x,y)). A value of 0 causes the arc to be drawn in a "negative-angle" direction (i.e., theta starts at an angle value corresponding to the current point and decreases until the arc reaches (x,y)).

The following illustrates the four combinations of large-arc-flag and sweep-flag and the four different arcs that will be drawn based on the values of these flags. For each case, the following path data command was used:

<path d="M 125,75 a100,50 0 ?,? 100,50"
      style="fill:none; stroke:red; stroke-width:6"/>

where "?,?" is replaced by "0,0" "0,1" "1,0" and "1,1" to generate the four possible cases.

Illustration of flags in arc commands

View this example as SVG (SVG-enabled browsers only)

Refer to Elliptical arc implementation notes for detailed implementation notes for the path data elliptical arc commands.

8.3.9 The grammar for path data

The following notation is used in the Backus-Naur Form (BNF) description of the grammar for path data:

*: 0 or more
+: 1 or more
?: 0 or 1
(): grouping
|: separates alternatives
double quotes surround literals

The following is the BNF for SVG paths.

svg-path:
    wsp* moveto-drawto-command-групи? wsp*
moveto-drawto-command-групи:
    moveto-drawto-command-group
    | moveto-drawto-command-group wsp* moveto-drawto-command-групи
moveto-drawto-command-group:
    moveto wsp* drawto-commands?
drawto-commands:
    drawto-command
    | drawto-command wsp* drawto-commands
drawto-command:
    closepath
    | lineto
    | horizontal-lineto
    | vertical-lineto
    | curveto
    | smooth-curveto
    | quadratic-bezier-curveto
    | smooth-quadratic-bezier-curveto
    | elliptical-arc
moveto:
    ( "M" | "m" ) wsp* moveto-argument-sequence
moveto-argument-sequence:
    coordinate-pair
    | coordinate-pair comma-wsp? lineto-argument-sequence
closepath:
    ("Z" | "z")
lineto:
    ( "L" | "l" ) wsp* lineto-argument-sequence
lineto-argument-sequence:
    coordinate-pair
    | coordinate-pair comma-wsp? lineto-argument-sequence
horizontal-lineto:
    ( "H" | "h" ) wsp* horizontal-lineto-argument-sequence
horizontal-lineto-argument-sequence:
    coordinate
    | coordinate comma-wsp? horizontal-lineto-argument-sequence
vertical-lineto:
    ( "V" | "v" ) wsp* vertical-lineto-argument-sequence
vertical-lineto-argument-sequence:
    coordinate
    | coordinate comma-wsp? vertical-lineto-argument-sequence
curveto:
    ( "C" | "c" ) wsp* curveto-argument-sequence
curveto-argument-sequence:
    curveto-argument
    | curveto-argument comma-wsp? curveto-argument-sequence
curveto-argument:
    coordinate-pair comma-wsp? coordinate-pair comma-wsp? coordinate-pair
smooth-curveto:
    ( "S" | "s" ) wsp* smooth-curveto-argument-sequence
smooth-curveto-argument-sequence:
    smooth-curveto-argument
    | smooth-curveto-argument comma-wsp? smooth-curveto-argument-sequence
smooth-curveto-argument:
    coordinate-pair comma-wsp? coordinate-pair
quadratic-bezier-curveto:
    ( "Q" | "q" ) wsp* quadratic-bezier-curveto-argument-sequence
quadratic-bezier-curveto-argument-sequence:
    quadratic-bezier-curveto-argument
    | quadratic-bezier-curveto-argument comma-wsp? 
        quadratic-bezier-curveto-argument-sequence
quadratic-bezier-curveto-argument:
    coordinate-pair comma-wsp? coordinate-pair
smooth-quadratic-bezier-curveto:
    ( "T" | "t" ) wsp* smooth-quadratic-bezier-curveto-argument-sequence
smooth-quadratic-bezier-curveto-argument-sequence:
    coordinate-pair
    | coordinate-pair comma-wsp? smooth-quadratic-bezier-curveto-argument-sequence
elliptical-arc:
    ( "A" | "a" ) wsp* elliptical-arc-argument-sequence
elliptical-arc-argument-sequence:
    elliptical-arc-argument
    | elliptical-arc-argument comma-wsp? elliptical-arc-argument-sequence
elliptical-arc-argument:
    nonnegative-number comma-wsp? nonnegative-number comma-wsp? 
        number comma-wsp flag comma-wsp? flag comma-wsp? coordinate-pair
coordinate-pair:
    coordinate comma-wsp? coordinate
coordinate:
    number
nonnegative-number:
    integer-constant
    | floating-point-constant
number:
    sign? integer-constant
    | sign? floating-point-constant
flag:
    "0" | "1"
comma-wsp:
    (wsp+ comma? wsp*) | (comma wsp*)
comma:
    ","
integer-constant:
    digit-sequence
floating-point-constant:
    fractional-constant exponent?
    | digit-sequence exponent
fractional-constant:
    digit-sequence? "." digit-sequence
    | digit-sequence "."
exponent:
    ( "e" | "E" ) sign? digit-sequence
sign:
    "+" | "-"
digit-sequence:
    digit
    | digit digit-sequence
digit:
    "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
wsp:
    (#x20 | #x9 | #xD | #xA)

The processing of the BNF must consume as much of a given BNF production as possible, stopping at the point when a character is encountered which no longer satisfies the production. Thus, in the string "M 100-200", the first coordinate for the "moveto" consumes the characters "100" and stops upon encountering the minus sign because the minus sign cannot follow a digit in the production of a "coordinate". The result is that the first coordinate will be "100" and the second coordinate will be "-200".

Similarly, for the string "M 0.6.5", the first coordinate of the "moveto" consumes the characters "0.6" and stops upon encountering the second decimal point because the production of a "coordinate" only allows one decimal point. The result is that the first coordinate will be "0.6" and the second coordinate will be ".5".

Note that the BNF allows the path ‘d’ атрибут to be empty. This is not an error, instead it disables rendering of the path.

8.4 Distance along a path

Various operations, including text on a path and motion animation and various stroke operations, require that the user agent compute the distance along the geometry of a graphics елемент, such as a ‘path’.

Exact mathematics exist for computing distance along a path, but the formulas are highly complex and require substantial computation. It is recommended that authoring products and user agents employ algorithms that produce as precise results as possible; however, to accommodate implementation differences and to help distance calculations produce results that approximate author intent, the ‘pathLength’ атрибут can be used to provide the author's computation of the total length of the path so that the user agent can scale distance-along-a-path computations by the ratio of ‘pathLength’ to the user agent's own computed value for total path length.

A "moveto" operation within a ‘path’ елемент is defined to have zero length. Only the various "lineto", "curveto" and "arcto" commands contribute to path length calculations.

8.5 DOM interfaces

8.5.1 Інтерфейс SVGPathSeg

The SVGPathSeg interface is a base interface that corresponds to a single command within a path data specification.

interface SVGPathSeg {

  // Path Segment Types
  const unsigned short PATHSEG_UNKNOWN = 0;
  const unsigned short PATHSEG_CLOSEPATH = 1;
  const unsigned short PATHSEG_MOVETO_ABS = 2;
  const unsigned short PATHSEG_MOVETO_REL = 3;
  const unsigned short PATHSEG_LINETO_ABS = 4;
  const unsigned short PATHSEG_LINETO_REL = 5;
  const unsigned short PATHSEG_CURVETO_CUBIC_ABS = 6;
  const unsigned short PATHSEG_CURVETO_CUBIC_REL = 7;
  const unsigned short PATHSEG_CURVETO_QUADRATIC_ABS = 8;
  const unsigned short PATHSEG_CURVETO_QUADRATIC_REL = 9;
  const unsigned short PATHSEG_ARC_ABS = 10;
  const unsigned short PATHSEG_ARC_REL = 11;
  const unsigned short PATHSEG_LINETO_HORIZONTAL_ABS = 12;
  const unsigned short PATHSEG_LINETO_HORIZONTAL_REL = 13;
  const unsigned short PATHSEG_LINETO_VERTICAL_ABS = 14;
  const unsigned short PATHSEG_LINETO_VERTICAL_REL = 15;
  const unsigned short PATHSEG_CURVETO_CUBIC_SMOOTH_ABS = 16;
  const unsigned short PATHSEG_CURVETO_CUBIC_SMOOTH_REL = 17;
  const unsigned short PATHSEG_CURVETO_QUADRATIC_SMOOTH_ABS = 18;
  const unsigned short PATHSEG_CURVETO_QUADRATIC_SMOOTH_REL = 19;

  readonly атрибут unsigned short pathSegType;
  readonly атрибут DOMString pathSegTypeAsLetter;
};

Constants in group “Path Segment Types”:

PATHSEG_UNKNOWN (unsigned short): The unit type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
PATHSEG_CLOSEPATH (unsigned short): Corresponds to a "closepath" (z) path data command.
PATHSEG_MOVETO_ABS (unsigned short): Corresponds to a "absolute moveto" (M) path data command.
PATHSEG_MOVETO_REL (unsigned short): Corresponds to a "relative moveto" (m) path data command.
PATHSEG_LINETO_ABS (unsigned short): Corresponds to a "absolute lineto" (L) path data command.
PATHSEG_LINETO_REL (unsigned short): Corresponds to a "relative lineto" (l) path data command.
PATHSEG_CURVETO_CUBIC_ABS (unsigned short): Corresponds to a "absolute cubic Bézier curveto" (C) path data command.
PATHSEG_CURVETO_CUBIC_REL (unsigned short): Corresponds to a "relative cubic Bézier curveto" (c) path data command.
PATHSEG_CURVETO_QUADRATIC_ABS (unsigned short): Corresponds to a "absolute quadratic Bézier curveto" (Q) path data command.
PATHSEG_CURVETO_QUADRATIC_REL (unsigned short): Corresponds to a "relative quadratic Bézier curveto" (q) path data command.
PATHSEG_ARC_ABS (unsigned short): Corresponds to a "absolute arcto" (A) path data command.
PATHSEG_ARC_REL (unsigned short): Corresponds to a "relative arcto" (a) path data command.
PATHSEG_LINETO_HORIZONTAL_ABS (unsigned short): Corresponds to a "absolute horizontal lineto" (H) path data command.
PATHSEG_LINETO_HORIZONTAL_REL (unsigned short): Corresponds to a "relative horizontal lineto" (h) path data command.
PATHSEG_LINETO_VERTICAL_ABS (unsigned short): Corresponds to a "absolute vertical lineto" (V) path data command.
PATHSEG_LINETO_VERTICAL_REL (unsigned short): Corresponds to a "relative vertical lineto" (v) path data command.
PATHSEG_CURVETO_CUBIC_SMOOTH_ABS (unsigned short): Corresponds to a "absolute smooth cubic curveto" (S) path data command.
PATHSEG_CURVETO_CUBIC_SMOOTH_REL (unsigned short): Corresponds to a "relative smooth cubic curveto" (s) path data command.
PATHSEG_CURVETO_QUADRATIC_SMOOTH_ABS (unsigned short): Corresponds to a "absolute smooth quadratic curveto" (T) path data command.
PATHSEG_CURVETO_QUADRATIC_SMOOTH_REL (unsigned short): Corresponds to a "relative smooth quadratic curveto" (t) path data command.

Attributes:

pathSegType (readonly unsigned short): The type of the path segment as specified by one of the constants defined on this interface.
pathSegTypeAsLetter (readonly DOMString): The type of the path segment, specified by the corresponding one character command name.

8.5.2 Інтерфейс SVGPathSegClosePath

The SVGPathSegClosePath interface corresponds to a "closepath" (z) path data command.

interface SVGPathSegClosePath : SVGPathSeg {
};

8.5.3 Інтерфейс SVGPathSegMovetoAbs

The SVGPathSegMovetoAbs interface corresponds to an "absolute moveto" (M) path data command.

interface SVGPathSegMovetoAbs : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
};

Attributes:

x (float)

The absolute X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The absolute Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.4 Інтерфейс SVGPathSegMovetoRel

The SVGPathSegMovetoRel interface corresponds to a "relative moveto" (m) path data command.

interface SVGPathSegMovetoRel : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
};

Attributes:

x (float)

The relative X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The relative Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.5 Інтерфейс SVGPathSegLinetoAbs

The SVGPathSegLinetoAbs interface corresponds to an "absolute lineto" (L) path data command.

interface SVGPathSegLinetoAbs : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
};

Attributes:

x (float)

The absolute X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The absolute Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.6 Інтерфейс SVGPathSegLinetoRel

The SVGPathSegLinetoRel interface corresponds to a "relative lineto" (l) path data command.

interface SVGPathSegLinetoRel : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
};

Attributes:

x (float)

The relative X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The relative Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.7 Інтерфейс SVGPathSegCurvetoCubicAbs

The SVGPathSegCurvetoCubicAbs interface corresponds to an "absolute cubic Bézier curveto" (C) path data command.

interface SVGPathSegCurvetoCubicAbs : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float x1 setraises(DOMException);
  атрибут float y1 setraises(DOMException);
  атрибут float x2 setraises(DOMException);
  атрибут float y2 setraises(DOMException);
};

Attributes:

x (float)

The absolute X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The absolute Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x1 (float)

The absolute X coordinate for the first control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y1 (float)

The absolute Y coordinate for the first control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x2 (float)

The absolute X coordinate for the second control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y2 (float)

The absolute Y coordinate for the second control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.8 Інтерфейс SVGPathSegCurvetoCubicRel

The SVGPathSegCurvetoCubicRel interface corresponds to a "relative cubic Bézier curveto" (c) path data command.

interface SVGPathSegCurvetoCubicRel : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float x1 setraises(DOMException);
  атрибут float y1 setraises(DOMException);
  атрибут float x2 setraises(DOMException);
  атрибут float y2 setraises(DOMException);
};

Attributes:

x (float)

The relative X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The relative Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x1 (float)

The relative X coordinate for the first control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y1 (float)

The relative Y coordinate for the first control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x2 (float)

The relative X coordinate for the second control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y2 (float)

The relative Y coordinate for the second control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.9 Інтерфейс SVGPathSegCurvetoQuadraticAbs

The SVGPathSegCurvetoQuadraticAbs interface corresponds to an "absolute quadratic Bézier curveto" (Q) path data command.

interface SVGPathSegCurvetoQuadraticAbs : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float x1 setraises(DOMException);
  атрибут float y1 setraises(DOMException);
};

Attributes:

x (float)

The absolute X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The absolute Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x1 (float)

The absolute X coordinate for the first control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y1 (float)

The absolute Y coordinate for the first control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.10 Інтерфейс SVGPathSegCurvetoQuadraticRel

The SVGPathSegCurvetoQuadraticRel interface corresponds to a "relative quadratic Bézier curveto" (q) path data command.

interface SVGPathSegCurvetoQuadraticRel : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float x1 setraises(DOMException);
  атрибут float y1 setraises(DOMException);
};

Attributes:

x (float)

The relative X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The relative Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x1 (float)

The relative X coordinate for the first control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y1 (float)

The relative Y coordinate for the first control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.11 Інтерфейс SVGPathSegArcAbs

The SVGPathSegArcAbs interface corresponds to an "absolute arcto" (A) path data command.

interface SVGPathSegArcAbs : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float r1 setraises(DOMException);
  атрибут float r2 setraises(DOMException);
  атрибут float angle setraises(DOMException);
  атрибут boolean largeArcFlag setraises(DOMException);
  атрибут boolean sweepFlag setraises(DOMException);
};

Attributes:

x (float)

The absolute X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The absolute Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

r1 (float)

The x-axis radius for the ellipse (i.e., r1).

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

r2 (float)

The y-axis radius for the ellipse (i.e., r2).

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

angle (float)

The rotation angle in degrees for the ellipse's x-axis relative to the x-axis of the user coordinate system.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

largeArcFlag (boolean)

The value of the large-arc-flag parameter.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

sweepFlag (boolean)

The value of the sweep-flag parameter.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.12 Інтерфейс SVGPathSegArcRel

The SVGPathSegArcRel interface corresponds to a "relative arcto" (a) path data command.

interface SVGPathSegArcRel : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float r1 setraises(DOMException);
  атрибут float r2 setraises(DOMException);
  атрибут float angle setraises(DOMException);
  атрибут boolean largeArcFlag setraises(DOMException);
  атрибут boolean sweepFlag setraises(DOMException);
};

Attributes:

x (float)

The relative X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The relative Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

r1 (float)

The x-axis radius for the ellipse (i.e., r1).

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

r2 (float)

The y-axis radius for the ellipse (i.e., r2).

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

angle (float)

The rotation angle in degrees for the ellipse's x-axis relative to the x-axis of the user coordinate system.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

largeArcFlag (boolean)

The value of the large-arc-flag parameter.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

sweepFlag (boolean)

The value of the sweep-flag parameter.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.13 Інтерфейс SVGPathSegLinetoHorizontalAbs

The SVGPathSegLinetoHorizontalAbs interface corresponds to an "absolute horizontal lineto" (H) path data command.

interface SVGPathSegLinetoHorizontalAbs : SVGPathSeg {
  атрибут float x setraises(DOMException);
};

Attributes:

x (float)

The absolute X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.14 Інтерфейс SVGPathSegLinetoHorizontalRel

The SVGPathSegLinetoHorizontalRel interface corresponds to a "relative horizontal lineto" (h) path data command.

interface SVGPathSegLinetoHorizontalRel : SVGPathSeg {
  атрибут float x setraises(DOMException);
};

Attributes:

x (float)

The relative X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.15 Інтерфейс SVGPathSegLinetoVerticalAbs

The SVGPathSegLinetoVerticalAbs interface corresponds to an "absolute vertical lineto" (V) path data command.

interface SVGPathSegLinetoVerticalAbs : SVGPathSeg {
  атрибут float y setraises(DOMException);
};

Attributes:

y (float)

The absolute Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.16 Інтерфейс SVGPathSegLinetoVerticalRel

The SVGPathSegLinetoVerticalRel interface corresponds to a "relative vertical lineto" (v) path data command.

interface SVGPathSegLinetoVerticalRel : SVGPathSeg {
  атрибут float y setraises(DOMException);
};

Attributes:

y (float)

The relative Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.17 Інтерфейс SVGPathSegCurvetoCubicSmoothAbs

The SVGPathSegCurvetoCubicSmoothAbs interface corresponds to an "absolute smooth cubic curveto" (S) path data command.

interface SVGPathSegCurvetoCubicSmoothAbs : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float x2 setraises(DOMException);
  атрибут float y2 setraises(DOMException);
};

Attributes:

x (float)

The absolute X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The absolute Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x2 (float)

The absolute X coordinate for the second control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y2 (float)

The absolute Y coordinate for the second control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.18 Інтерфейс SVGPathSegCurvetoCubicSmoothRel

The SVGPathSegCurvetoCubicSmoothRel interface corresponds to a "relative smooth cubic curveto" (s) path data command.

interface SVGPathSegCurvetoCubicSmoothRel : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float x2 setraises(DOMException);
  атрибут float y2 setraises(DOMException);
};

Attributes:

x (float)

The relative X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The relative Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x2 (float)

The relative X coordinate for the second control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y2 (float)

The relative Y coordinate for the second control point.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.19 Інтерфейс SVGPathSegCurvetoQuadraticSmoothAbs

The SVGPathSegCurvetoQuadraticSmoothAbs interface corresponds to an "absolute smooth cubic curveto" (T) path data command.

interface SVGPathSegCurvetoQuadraticSmoothAbs : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
};

Attributes:

x (float)

The absolute X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The absolute Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.20 Інтерфейс SVGPathSegCurvetoQuadraticSmoothRel

The SVGPathSegCurvetoQuadraticSmoothRel interface corresponds to a "relative smooth cubic curveto" (t) path data command.

interface SVGPathSegCurvetoQuadraticSmoothRel : SVGPathSeg {
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
};

Attributes:

x (float)

The relative X coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

The relative Y coordinate for the end point of this path segment.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

8.5.21 Інтерфейс SVGPathSegList

This interface defines a list of SVGPathSeg objects.

SVGPathSegList has the same атрибути and methods as other SVGxxxList interfaces. Implementers may consider using a single base class to implement the various SVGxxxList interfaces.

interface SVGPathSegList {

  readonly атрибут unsigned long numberOfItems;

  void clear() raises(DOMException);
  SVGPathSeg initialize(in SVGPathSeg newItem) raises(DOMException);
  SVGPathSeg getItem(in unsigned long index) raises(DOMException);
  SVGPathSeg insertItemBefore(in SVGPathSeg newItem, in unsigned long index) raises(DOMException);
  SVGPathSeg replaceItem(in SVGPathSeg newItem, in unsigned long index) raises(DOMException);
  SVGPathSeg removeItem(in unsigned long index) raises(DOMException);
  SVGPathSeg appendItem(in SVGPathSeg newItem) raises(DOMException);
};

Attributes:

numberOfItems (readonly unsigned long): The number of items in the list.

Operations:

void clear()

Clears all existing current items from the list, with the result being an empty list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

SVGPathSeg initialize(in SVGPathSeg newItem)

Parameters

SVGPathSeg newItem

The item which should become the only member of the list.

Returns

The item being inserted into the list.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

SVGPathSeg getItem(in unsigned long index)

Returns the specified item from the list. The returned item is the item itself and not a copy. Any changes made to the item are immediately reflected in the list.

Parameters

unsigned long index

The index of the item from the list which is to be returned. The first item is number 0.

Returns

The selected item.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGPathSeg insertItemBefore(in SVGPathSeg newItem, in unsigned long index)

Parameters

SVGPathSeg newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item before which the new item is to be inserted. The first item is number 0. If the index is equal to 0, then the new item is inserted at the front of the list. If the index is greater than or equal to numberOfItems, then the new item is appended to the end of the list.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

SVGPathSeg replaceItem(in SVGPathSeg newItem, in unsigned long index)

Parameters

SVGPathSeg newItem

The item which is to be inserted into the list.
unsigned long index

The index of the item which is to be replaced. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGPathSeg removeItem(in unsigned long index)

Removes an existing item from the list.

Parameters

unsigned long index

The index of the item which is to be removed. The first item is number 0.

Returns

The removed item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.
DOMException, code INDEX_SIZE_ERR: Raised if the index number is greater than or equal to numberOfItems.

SVGPathSeg appendItem(in SVGPathSeg newItem)

Parameters

SVGPathSeg newItem

The item which is to be inserted. The first item is number 0.

Returns

The inserted item.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised when the list cannot be modified.

8.5.22 Інтерфейс SVGAnimatedPathData

The SVGAnimatedPathData interface supports елементи which have a ‘d’ атрибут which holds SVG path data, and supports the ability to animate that атрибут.

The SVGAnimatedPathData interface provides two lists to access and modify the base (i.e., static) contents of the ‘d’ атрибут:

DOM атрибут pathSegList provides access to the static/base contents of the ‘d’ атрибут in a form which matches one-for-one with SVG's syntax.
DOM атрибут normalizedPathSegList provides normalized access to the static/base contents of the ‘d’ атрибут where all path data commands are expressed in terms of the following subset of SVGPathSeg types: SVG_PATHSEG_MOVETO_ABS (M), SVG_PATHSEG_LINETO_ABS (L), SVG_PATHSEG_CURVETO_CUBIC_ABS (C) and SVG_PATHSEG_CLOSEPATH (z).

and two lists to access the current animated values of the ‘d’ атрибут:

DOM атрибут animatedPathSegList provides access to the current animated contents of the ‘d’ атрибут in a form which matches one-for-one with SVG's syntax.
DOM атрибут animatedNormalizedPathSegList provides normalized access to the current animated contents of the ‘d’ атрибут where all path data commands are expressed in terms of the following subset of SVGPathSeg types: SVG_PATHSEG_MOVETO_ABS (M), SVG_PATHSEG_LINETO_ABS (L), SVG_PATHSEG_CURVETO_CUBIC_ABS (C) and SVG_PATHSEG_CLOSEPATH (z).

Each of the two lists are always kept synchronized. Modifications to one list will immediately cause the corresponding list to be modified. Modifications to normalizedPathSegList might cause entries in pathSegList to be broken into a set of normalized path segments.

Additionally, the ‘d’ атрибут on the ‘path’ елемент accessed via the XML DOM (e.g., using the getAttribute() method call) will reflect any changes made to pathSegList or normalizedPathSegList.

interface SVGAnimatedPathData {
  readonly атрибут SVGPathSegList pathSegList;
  readonly атрибут SVGPathSegList normalizedPathSegList;
  readonly атрибут SVGPathSegList animatedPathSegList;
  readonly атрибут SVGPathSegList animatedNormalizedPathSegList;
};

Attributes:

pathSegList (readonly SVGPathSegList): Provides access to the base (i.e., static) contents of the ‘d’ атрибут in a form which matches one-for-one with SVG's syntax. Thus, if the ‘d’ атрибут has an "absolute moveto (M)" and an "absolute arcto (A)" command, then pathSegList will have two entries: a SVG_PATHSEG_MOVETO_ABS and a SVG_PATHSEG_ARC_ABS.
normalizedPathSegList (readonly SVGPathSegList): Provides access to the base (i.e., static) contents of the ‘d’ атрибут in a form where all path data commands are expressed in terms of the following subset of SVGPathSeg types: SVG_PATHSEG_MOVETO_ABS (M), SVG_PATHSEG_LINETO_ABS (L), SVG_PATHSEG_CURVETO_CUBIC_ABS (C) and SVG_PATHSEG_CLOSEPATH (z). Thus, if the ‘d’ атрибут has an "absolute moveto (M)" and an "absolute arcto (A)" command, then pathSegList will have one SVG_PATHSEG_MOVETO_ABS entry followed by a series of SVG_PATHSEG_LINETO_ABS entries which approximate the arc. This alternate representation is available to provide a simpler interface to developers who would benefit from a more limited set of commands.

The only valid SVGPathSeg types are SVG_PATHSEG_MOVETO_ABS (M), SVG_PATHSEG_LINETO_ABS (L), SVG_PATHSEG_CURVETO_CUBIC_ABS (C) and SVG_PATHSEG_CLOSEPATH (z).
animatedPathSegList (readonly SVGPathSegList): Provides access to the current animated contents of the ‘d’ атрибут in a form which matches one-for-one with SVG's syntax. If the given атрибут or властивість is being animated, contains the current animated value of the атрибут or властивість, and both the object itself and its contents are read only. If the given атрибут or властивість is not currently being animated, contains the same value as pathSegList.
animatedNormalizedPathSegList (readonly SVGPathSegList): Provides access to the current animated contents of the ‘d’ атрибут in a form where all path data commands are expressed in terms of the following subset of SVGPathSeg types: SVG_PATHSEG_MOVETO_ABS (M), SVG_PATHSEG_LINETO_ABS (L), SVG_PATHSEG_CURVETO_CUBIC_ABS (C) and SVG_PATHSEG_CLOSEPATH (z). If the given атрибут or властивість is being animated, contains the current animated value of the атрибут or властивість, and both the object itself and its contents are read only. If the given атрибут or властивість is not currently being animated, contains the same value as normalizedPathSegList.

8.5.23 Інтерфейс SVGPathElement

The SVGPathElement interface corresponds to the ‘path’ елемент.

interface SVGPathElement : SVGElement,
                           SVGTests,
                           SVGLangSpace,
                           SVGExternalResourcesRequired,
                           SVGStylable,
                           SVGTransformable,
                           SVGAnimatedPathData {

  readonly атрибут SVGAnimatedNumber pathLength;

  float getTotalLength();
  SVGPoint getPointAtLength(in float distance);
  unsigned long getPathSegAtLength(in float distance);
  SVGPathSegClosePath createSVGPathSegClosePath();
  SVGPathSegMovetoAbs createSVGPathSegMovetoAbs(in float x, in float y);
  SVGPathSegMovetoRel createSVGPathSegMovetoRel(in float x, in float y);
  SVGPathSegLinetoAbs createSVGPathSegLinetoAbs(in float x, in float y);
  SVGPathSegLinetoRel createSVGPathSegLinetoRel(in float x, in float y);
  SVGPathSegCurvetoCubicAbs createSVGPathSegCurvetoCubicAbs(in float x, in float y, in float x1, in float y1, in float x2, in float y2);
  SVGPathSegCurvetoCubicRel createSVGPathSegCurvetoCubicRel(in float x, in float y, in float x1, in float y1, in float x2, in float y2);
  SVGPathSegCurvetoQuadraticAbs createSVGPathSegCurvetoQuadraticAbs(in float x, in float y, in float x1, in float y1);
  SVGPathSegCurvetoQuadraticRel createSVGPathSegCurvetoQuadraticRel(in float x, in float y, in float x1, in float y1);
  SVGPathSegArcAbs createSVGPathSegArcAbs(in float x, in float y, in float r1, in float r2, in float angle, in boolean largeArcFlag, in boolean sweepFlag);
  SVGPathSegArcRel createSVGPathSegArcRel(in float x, in float y, in float r1, in float r2, in float angle, in boolean largeArcFlag, in boolean sweepFlag);
  SVGPathSegLinetoHorizontalAbs createSVGPathSegLinetoHorizontalAbs(in float x);
  SVGPathSegLinetoHorizontalRel createSVGPathSegLinetoHorizontalRel(in float x);
  SVGPathSegLinetoVerticalAbs createSVGPathSegLinetoVerticalAbs(in float y);
  SVGPathSegLinetoVerticalRel createSVGPathSegLinetoVerticalRel(in float y);
  SVGPathSegCurvetoCubicSmoothAbs createSVGPathSegCurvetoCubicSmoothAbs(in float x, in float y, in float x2, in float y2);
  SVGPathSegCurvetoCubicSmoothRel createSVGPathSegCurvetoCubicSmoothRel(in float x, in float y, in float x2, in float y2);
  SVGPathSegCurvetoQuadraticSmoothAbs createSVGPathSegCurvetoQuadraticSmoothAbs(in float x, in float y);
  SVGPathSegCurvetoQuadraticSmoothRel createSVGPathSegCurvetoQuadraticSmoothRel(in float x, in float y);
};

Attributes:

pathLength (readonly SVGAnimatedNumber): Corresponds to атрибут pathLength on the given ‘path’ елемент.

Operations:

float getTotalLength()

Returns the user agent's computed value for the total length of the path using the user agent's distance-along-a-path algorithm, as a distance in the current user coordinate system.

Returns: The total length of the path.

SVGPoint getPointAtLength(in float distance)

Returns the (x,y) coordinate in user space which is distance units along the path, utilizing the user agent's distance-along-a-path algorithm.

Parameters

float distance

The distance along the path, relative to the start of the path, as a distance in the current user coordinate system.

Returns

The returned point in user space.

unsigned long getPathSegAtLength(in float distance)

Returns the index into pathSegList which is distance units along the path, utilizing the user agent's distance-along-a-path algorithm.

Parameters

float distance

The distance along the path, relative to the start of the path, as a distance in the current user coordinate system.

Returns

The index of the path segment, where the first path segment is number 0.

SVGPathSegClosePath createSVGPathSegClosePath()

Returns a stand-alone, parentless SVGPathSegClosePath object.

Returns: A stand-alone, parentless SVGPathSegClosePath object.

SVGPathSegMovetoAbs createSVGPathSegMovetoAbs(in float x, in float y)

Returns a stand-alone, parentless SVGPathSegMovetoAbs object.

Parameters

float x

The absolute X coordinate for the end point of this path segment.
float y

The absolute Y coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegMovetoAbs object.

SVGPathSegMovetoRel createSVGPathSegMovetoRel(in float x, in float y)

Returns a stand-alone, parentless SVGPathSegMovetoRel object.

Parameters

float x

The relative X coordinate for the end point of this path segment.
float y

The relative Y coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegMovetoRel object.

SVGPathSegLinetoAbs createSVGPathSegLinetoAbs(in float x, in float y)

Returns a stand-alone, parentless SVGPathSegLinetoAbs object.

Parameters

float x

The absolute X coordinate for the end point of this path segment.
float y

The absolute Y coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegLinetoAbs object.

SVGPathSegLinetoRel createSVGPathSegLinetoRel(in float x, in float y)

Returns a stand-alone, parentless SVGPathSegLinetoRel object.

Parameters

float x

The relative X coordinate for the end point of this path segment.
float y

The relative Y coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegLinetoRel object.

SVGPathSegCurvetoCubicAbs createSVGPathSegCurvetoCubicAbs(in float x, in float y, in float x1, in float y1, in float x2, in float y2)

Returns a stand-alone, parentless SVGPathSegCurvetoCubicAbs object.

Parameters

float x

The absolute X coordinate for the end point of this path segment.
float y

The absolute Y coordinate for the end point of this path segment.
float x1

The absolute X coordinate for the first control point.
float y1

The absolute Y coordinate for the first control point.
float x2

The absolute X coordinate for the second control point.
float y2

The absolute Y coordinate for the second control point.

Returns

A stand-alone, parentless SVGPathSegCurvetoCubicAbs object.

SVGPathSegCurvetoCubicRel createSVGPathSegCurvetoCubicRel(in float x, in float y, in float x1, in float y1, in float x2, in float y2)

Returns a stand-alone, parentless SVGPathSegCurvetoCubicRel object.

Parameters

float x

The relative X coordinate for the end point of this path segment.
float y

The relative Y coordinate for the end point of this path segment.
float x1

The relative X coordinate for the first control point.
float y1

The relative Y coordinate for the first control point.
float x2

The relative X coordinate for the second control point.
float y2

The relative Y coordinate for the second control point.

Returns

A stand-alone, parentless SVGPathSegCurvetoCubicRel object.

SVGPathSegCurvetoQuadraticAbs createSVGPathSegCurvetoQuadraticAbs(in float x, in float y, in float x1, in float y1)

Returns a stand-alone, parentless SVGPathSegCurvetoQuadraticAbs object.

Parameters

float x

The absolute X coordinate for the end point of this path segment.
float y

The absolute Y coordinate for the end point of this path segment.
float x1

The absolute X coordinate for the first control point.
float y1

The absolute Y coordinate for the first control point.

Returns

A stand-alone, parentless SVGPathSegCurvetoQuadraticAbs object.

SVGPathSegCurvetoQuadraticRel createSVGPathSegCurvetoQuadraticRel(in float x, in float y, in float x1, in float y1)

Returns a stand-alone, parentless SVGPathSegCurvetoQuadraticRel object.

Parameters

float x

The relative X coordinate for the end point of this path segment.
float y

The relative Y coordinate for the end point of this path segment.
float x1

The relative X coordinate for the first control point.
float y1

The relative Y coordinate for the first control point.

Returns

A stand-alone, parentless SVGPathSegCurvetoQuadraticRel object.

SVGPathSegArcAbs createSVGPathSegArcAbs(in float x, in float y, in float r1, in float r2, in float angle, in boolean largeArcFlag, in boolean sweepFlag)

Returns a stand-alone, parentless SVGPathSegArcAbs object.

Parameters

float x

The absolute X coordinate for the end point of this path segment.
float y

The absolute Y coordinate for the end point of this path segment.
float r1

The x-axis radius for the ellipse (i.e., r1).
float r2

The y-axis radius for the ellipse (i.e., r2).
float angle

The rotation angle in degrees for the ellipse's x-axis relative to the x-axis of the user coordinate system.
boolean largeArcFlag

The value of the large-arc-flag parameter.
boolean sweepFlag

The value of the large-arc-flag parameter.

Returns

A stand-alone, parentless SVGPathSegArcAbs object.

SVGPathSegArcRel createSVGPathSegArcRel(in float x, in float y, in float r1, in float r2, in float angle, in boolean largeArcFlag, in boolean sweepFlag)

Returns a stand-alone, parentless SVGPathSegArcRel object.

Parameters

float x

The relative X coordinate for the end point of this path segment.
float y

The relative Y coordinate for the end point of this path segment.
float r1

The x-axis radius for the ellipse (i.e., r1).
float r2

The y-axis radius for the ellipse (i.e., r2).
float angle

The rotation angle in degrees for the ellipse's x-axis relative to the x-axis of the user coordinate system.
boolean largeArcFlag

The value of the large-arc-flag parameter.
boolean sweepFlag

The value of the large-arc-flag parameter.

Returns

A stand-alone, parentless SVGPathSegArcRel object.

SVGPathSegLinetoHorizontalAbs createSVGPathSegLinetoHorizontalAbs(in float x)

Returns a stand-alone, parentless SVGPathSegLinetoHorizontalAbs object.

Parameters

float x

The absolute X coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegLinetoHorizontalAbs object.

SVGPathSegLinetoHorizontalRel createSVGPathSegLinetoHorizontalRel(in float x)

Returns a stand-alone, parentless SVGPathSegLinetoHorizontalRel object.

Parameters

float x

The relative X coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegLinetoHorizontalRel object.

SVGPathSegLinetoVerticalAbs createSVGPathSegLinetoVerticalAbs(in float y)

Returns a stand-alone, parentless SVGPathSegLinetoVerticalAbs object.

Parameters

float y

The absolute Y coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegLinetoVerticalAbs object.

SVGPathSegLinetoVerticalRel createSVGPathSegLinetoVerticalRel(in float y)

Returns a stand-alone, parentless SVGPathSegLinetoVerticalRel object.

Parameters

float y

The relative Y coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegLinetoVerticalRel object.

SVGPathSegCurvetoCubicSmoothAbs createSVGPathSegCurvetoCubicSmoothAbs(in float x, in float y, in float x2, in float y2)

Returns a stand-alone, parentless SVGPathSegCurvetoCubicSmoothAbs object.

Parameters

float x

The absolute X coordinate for the end point of this path segment.
float y

The absolute Y coordinate for the end point of this path segment.
float x2

The absolute X coordinate for the second control point.
float y2

The absolute Y coordinate for the second control point.

Returns

A stand-alone, parentless SVGPathSegCurvetoCubicSmoothAbs object.

SVGPathSegCurvetoCubicSmoothRel createSVGPathSegCurvetoCubicSmoothRel(in float x, in float y, in float x2, in float y2)

Returns a stand-alone, parentless SVGPathSegCurvetoCubicSmoothRel object.

Parameters

float x

The relative X coordinate for the end point of this path segment.
float y

The relative Y coordinate for the end point of this path segment.
float x2

The relative X coordinate for the second control point.
float y2

The relative Y coordinate for the second control point.

Returns

A stand-alone, parentless SVGPathSegCurvetoCubicSmoothRel object.

SVGPathSegCurvetoQuadraticSmoothAbs createSVGPathSegCurvetoQuadraticSmoothAbs(in float x, in float y)

Returns a stand-alone, parentless SVGPathSegCurvetoQuadraticSmoothAbs object.

Parameters

float x

The absolute X coordinate for the end point of this path segment.
float y

The absolute Y coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegCurvetoQuadraticSmoothAbs object.

SVGPathSegCurvetoQuadraticSmoothRel createSVGPathSegCurvetoQuadraticSmoothRel(in float x, in float y)

Returns a stand-alone, parentless SVGPathSegCurvetoQuadraticSmoothRel object.

Parameters

float x

The relative X coordinate for the end point of this path segment.
float y

The relative Y coordinate for the end point of this path segment.

Returns

A stand-alone, parentless SVGPathSegCurvetoQuadraticSmoothRel object.

9 Basic Shapes

9.1 Вступ
9.2 The ‘rect’ елемент
9.3 The ‘circle’ елемент
9.4 The ‘ellipse’ елемент
9.5 The ‘line’ елемент
9.6 The ‘polyline’ елемент
9.7 The ‘polygon’ елемент
- 9.7.1 The grammar for points specifications in ‘polyline’ and ‘polygon’ елементи
9.8 DOM interfaces

9.1 Вступ

SVG contains the following set of basic shape елементи:

rectangles (including optional rounded corners), created with the ‘rect’ елемент,
circles, created with the ‘circle’ елемент,
ellipses, created with the ‘ellipse’ елемент,
straight lines, created with the ‘line’ елемент,
polylines, created with the ‘polyline’ елемент, and
polygons, created with the ‘polygon’ елемент.

Mathematically, these shape елементи are equivalent to a ‘path’ елемент that would construct the same shape. The basic shapes may be stroked, filled and used as clip paths. All of the властивості available for ‘path’ елементи also apply to the basic shapes.

9.2 The ‘rect’ елемент

The ‘rect’ елемент defines a rectangle which is axis-aligned with the current user coordinate system. Rounded rectangles can be achieved by setting appropriate values for атрибути ‘rx’ and ‘ry’.

‘rect’

Categories:

Basic shape елемент, graphics елемент, shape елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘x’
‘y’
‘width’
‘height’
‘rx’
‘ry’

DOM Інтерфейсs:

SVGRectElement

Attribute definitions:

x = "<coordinate>": The x-axis coordinate of the side of the rectangle which has the smaller x-axis coordinate value in the current user coordinate system.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
y = "<coordinate>": The y-axis coordinate of the side of the rectangle which has the smaller y-axis coordinate value in the current user coordinate system.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
width = "<length>": The width of the rectangle.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
Animatable: yes.
height = "<length>": The height of the rectangle.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
Animatable: yes.
rx = "<length>": For rounded rectangles, the x-axis radius of the ellipse used to round off the corners of the rectangle.
A negative value is an error (see Error processing).
See the notes below about what happens if the атрибут is not specified.
Animatable: yes.
ry = "<length>": For rounded rectangles, the y-axis radius of the ellipse used to round off the corners of the rectangle.
A negative value is an error (see Error processing).
See the notes below about what happens if the атрибут is not specified.
Animatable: yes.

The values used for the x- and y-axis rounded corner radii are determined implicitly if the ‘rx’ or ‘ry’ атрибути (or both) are not specified, or are specified but with invalid values. The values are also subject to clamping so that the lengths of the straight segments of the rectangle are never negative. The effective values for ‘rx’ and ‘ry’ are determined by following these steps in order:

Let rx and ry be length values.
If neither ‘rx’ nor ‘ry’ are properly specified, then set both rx and ry to 0. (This will result in square corners.)
Otherwise, if a properly specified value is provided for ‘rx’, but not for ‘ry’, then set both rx and ry to the value of ‘rx’.
Otherwise, if a properly specified value is provided for ‘ry’, but not for ‘rx’, then set both rx and ry to the value of ‘ry’.
Otherwise, both ‘rx’ and ‘ry’ were specified properly. Set rx to the value of ‘rx’ and ry to the value of ‘ry’.
If rx is greater than half of ‘width’, then set rx to half of ‘width’.
If ry is greater than half of ‘height’, then set ry to half of ‘height’.
The effective values of ‘rx’ and ‘ry’ are rx and ry, respectively.

Mathematically, a ‘rect’ елемент can be mapped to an equivalent ‘path’ елемент as follows: (Note: all coordinate and length values are first converted into user space coordinates according to Units.)

perform an absolute moveto operation to location (x+rx,y), where x is the value of the ‘rect’ елемент's ‘x’ атрибут converted to user space, rx is the effective value of the ‘rx’ атрибут converted to user space and y is the value of the ‘y’ атрибут converted to user space
perform an absolute horizontal lineto operation to location (x+width-rx,y), where width is the ‘rect’ елемент's ‘width’ атрибут converted to user space
perform an absolute elliptical arc operation to coordinate (x+width,y+ry), where the effective values for the ‘rx’ and ‘ry’ атрибути on the ‘rect’ елемент converted to user space are used as the rx and ry атрибути on the elliptical arc command, respectively, the x-axis-rotation is set to zero, the large-arc-flag is set to zero, and the sweep-flag is set to one
perform a absolute vertical lineto to location (x+width,y+height-ry), where height is the ‘rect’ елемент's ‘height’ атрибут converted to user space
perform an absolute elliptical arc operation to coordinate (x+width-rx,y+height)
perform an absolute horizontal lineto to location (x+rx,y+height)
perform an absolute elliptical arc operation to coordinate (x,y+height-ry)
perform an absolute absolute vertical lineto to location (x,y+ry)
perform an absolute elliptical arc operation to coordinate (x+rx,y)

Example rect01 shows a rectangle with sharp corners. The ‘rect’ елемент is filled with yellow and stroked with navy.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="4cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example rect01 - rectangle with sharp corners</desc>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="1198" height="398"
        fill="none" stroke="blue" stroke-width="2"/>

  <rect x="400" y="100" width="400" height="200"
        fill="yellow" stroke="navy" stroke-width="10"  />
</svg>

Example rect01

View this example as SVG (SVG-enabled browsers only)

Example rect02 shows two rounded rectangles. The ‘rx’ specifies how to round the corners of the rectangles. Note that since no value has been specified for the ‘ry’ атрибут, it will be assigned the same value as the ‘rx’ атрибут.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="4cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example rect02 - rounded rectangles</desc>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="1198" height="398"
        fill="none" stroke="blue" stroke-width="2"/>

  <rect x="100" y="100" width="400" height="200" rx="50"
        fill="green" />

  <g transform="translate(700 210) rotate(-30)">
    <rect x="0" y="0" width="400" height="200" rx="50"
          fill="none" stroke="purple" stroke-width="30" />
  </g>
</svg>

Example rect02

View this example as SVG (SVG-enabled browsers only)

9.3 The ‘circle’ елемент

The ‘circle’ елемент defines a circle based on a center point and a radius.

‘circle’

Categories:

Basic shape елемент, graphics елемент, shape елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘cx’
‘cy’
‘r’

DOM Інтерфейсs:

SVGCircleElement

Attribute definitions:

cx = "<coordinate>": The x-axis coordinate of the center of the circle.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
cy = "<coordinate>": The y-axis coordinate of the center of the circle.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
r = "<length>": The radius of the circle.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
Animatable: yes.

The arc of a ‘circle’ елемент begins at the "3 o'clock" point on the radius and progresses towards the "9 o'clock" point. The starting point and direction of the arc are affected by the user space transform in the same manner as the geometry of the елемент.

Example circle01 consists of a ‘circle’ елемент that is filled with red and stroked with blue.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="4cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example circle01 - circle filled with red and stroked with blue</desc>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="1198" height="398"
        fill="none" stroke="blue" stroke-width="2"/>

  <circle cx="600" cy="200" r="100"
        fill="red" stroke="blue" stroke-width="10"  />
</svg>

Example circle01

View this example as SVG (SVG-enabled browsers only)

9.4 The ‘ellipse’ елемент

The ‘ellipse’ елемент defines an ellipse which is axis-aligned with the current user coordinate system based on a center point and two radii.

‘ellipse’

Categories:

Basic shape елемент, graphics елемент, shape елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘cx’
‘cy’
‘rx’
‘ry’

DOM Інтерфейсs:

SVGEllipseElement

Attribute definitions:

cx = "<coordinate>": The x-axis coordinate of the center of the ellipse.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
cy = "<coordinate>": The y-axis coordinate of the center of the ellipse.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
rx = "<length>": The x-axis radius of the ellipse.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
Animatable: yes.
ry = "<length>": The y-axis radius of the ellipse.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
Animatable: yes.

The arc of an ‘ellipse’ елемент begins at the "3 o'clock" point on the radius and progresses towards the "9 o'clock" point. The starting point and direction of the arc are affected by the user space transform in the same manner as the geometry of the елемент.

Example ellipse01 below specifies the coordinates of the two ellipses in the user coordinate system established by the ‘viewBox’ атрибут on the ‘svg’ елемент and the ‘transform’ атрибут on the ‘g’ and ‘ellipse’ елементи. Both ellipses use the default values of zero for the ‘cx’ and ‘cy’ атрибути (the center of the ellipse). The second ellipse is rotated.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="4cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example ellipse01 - examples of ellipses</desc>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="1198" height="398"
        fill="none" stroke="blue" stroke-width="2" />

  <g transform="translate(300 200)">
    <ellipse rx="250" ry="100"
          fill="red"  />
  </g>

  <ellipse transform="translate(900 200) rotate(-30)" 
        rx="250" ry="100"
        fill="none" stroke="blue" stroke-width="20"  />

</svg>

Example ellipse01

View this example as SVG (SVG-enabled browsers only)

9.5 The ‘line’ елемент

The ‘line’ елемент defines a line segment that starts at one point and ends at another.

‘line’

Categories:

Basic shape елемент, graphics елемент, shape елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘x1’
‘y1’
‘x2’
‘y2’

DOM Інтерфейсs:

SVGLineElement

Attribute definitions:

x1 = "<coordinate>": The x-axis coordinate of the start of the line.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
y1 = "<coordinate>": The y-axis coordinate of the start of the line.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
x2 = "<coordinate>": The x-axis coordinate of the end of the line.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
y2 = "<coordinate>": The y-axis coordinate of the end of the line.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.

Mathematically, a ‘line’ елемент can be mapped to an equivalent ‘path’ елемент as follows: (Note: all coordinate and length values are first converted into user space coordinates according to Units.)

perform an absolute moveto operation to absolute location (x1,y1), where x1 and y1 are the values of the ‘line’ елемент's ‘x1’ and ‘y1’ атрибути converted to user space, respectively
perform an absolute lineto operation to absolute location (x2,y2), where x2 and y2 are the values of the ‘line’ елемент's ‘x2’ and ‘y2’ атрибути converted to user space, respectively

Because ‘line’ елементи are single lines and thus are geometrically one-dimensional, they have no interior; thus, ‘line’ елементи are never filled (see the ‘fill’ властивість).

Example line01 below specifies the coordinates of the five lines in the user coordinate system established by the ‘viewBox’ атрибут on the ‘svg’ елемент. The lines have different thicknesses.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="4cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example line01 - lines expressed in user coordinates</desc>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="1198" height="398"
        fill="none" stroke="blue" stroke-width="2" />

  <g stroke="green" >
    <line x1="100" y1="300" x2="300" y2="100"
            stroke-width="5"  />
    <line x1="300" y1="300" x2="500" y2="100"
            stroke-width="10"  />
    <line x1="500" y1="300" x2="700" y2="100"
            stroke-width="15"  />
    <line x1="700" y1="300" x2="900" y2="100"
            stroke-width="20"  />
    <line x1="900" y1="300" x2="1100" y2="100"
            stroke-width="25"  />
  </g>
</svg>

Example line01

View this example as SVG (SVG-enabled browsers only)

9.6 The ‘polyline’ елемент

The ‘polyline’ елемент defines a set of connected straight line segments. Typically, ‘polyline’ елементи define open shapes.

‘polyline’

Categories:

Basic shape елемент, graphics елемент, shape елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘points’

DOM Інтерфейсs:

SVGPolylineElement

Attribute definitions:

points = "<list-of-points>": The points that make up the polyline. All coordinate values are in the user coordinate system.
Animatable: yes.

If an odd number of coordinates is provided, then the елемент is in error, with the same user agent behavior as occurs with an incorrectly specified ‘path’ елемент.

Mathematically, a ‘polyline’ елемент can be mapped to an equivalent ‘path’ елемент as follows:

perform an absolute moveto operation to the first coordinate pair in the list of points
for each subsequent coordinate pair, perform an absolute lineto operation to that coordinate pair.

Example polyline01 below specifies a polyline in the user coordinate system established by the ‘viewBox’ атрибут on the ‘svg’ елемент.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="4cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example polyline01 - increasingly larger bars</desc>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="1198" height="398"
        fill="none" stroke="blue" stroke-width="2" />

  <polyline fill="none" stroke="blue" stroke-width="10" 
            points="50,375
                    150,375 150,325 250,325 250,375
                    350,375 350,250 450,250 450,375
                    550,375 550,175 650,175 650,375
                    750,375 750,100 850,100 850,375
                    950,375 950,25 1050,25 1050,375
                    1150,375" />
</svg>

Example polyline01

View this example as SVG (SVG-enabled browsers only)

9.7 The ‘polygon’ елемент

The ‘polygon’ елемент defines a closed shape consisting of a set of connected straight line segments.

‘polygon’

Categories:

Basic shape елемент, graphics елемент, shape елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘points’

DOM Інтерфейсs:

SVGPolygonElement

Attribute definitions:

points = "<list-of-points>": The points that make up the polygon. All coordinate values are in the user coordinate system.
Animatable: yes.

If an odd number of coordinates is provided, then the елемент is in error, with the same user agent behavior as occurs with an incorrectly specified ‘path’ елемент.

Mathematically, a ‘polygon’ елемент can be mapped to an equivalent ‘path’ елемент as follows:

perform an absolute moveto operation to the first coordinate pair in the list of points
for each subsequent coordinate pair, perform an absolute lineto operation to that coordinate pair
perform a closepath command

Example polygon01 below specifies two polygons (a star and a hexagon) in the user coordinate system established by the ‘viewBox’ атрибут on the ‘svg’ елемент.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="4cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example polygon01 - star and hexagon</desc>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="1198" height="398"
        fill="none" stroke="blue" stroke-width="2" />

  <polygon fill="red" stroke="blue" stroke-width="10" 
            points="350,75  379,161 469,161 397,215
                    423,301 350,250 277,301 303,215
                    231,161 321,161" />
  <polygon fill="lime" stroke="blue" stroke-width="10" 
            points="850,75  958,137.5 958,262.5
                    850,325 742,262.6 742,137.5" />
</svg>

Example polygon01

View this example as SVG (SVG-enabled browsers only)

9.7.1 The grammar for points specifications in ‘polyline’ and ‘polygon’ елементи

The following is the Extended Backus-Naur Form (EBNF) for points specifications in ‘polyline’ and ‘polygon’ елементи. The following notation is used:

*: 0 or more
+: 1 or more
?: 0 or 1
(): grouping
|: separates alternatives
double quotes surround literals

list-of-points:
    wsp* coordinate-pairs? wsp*
coordinate-pairs:
    coordinate-pair
    | coordinate-pair comma-wsp coordinate-pairs
coordinate-pair:
    coordinate comma-wsp coordinate
    | coordinate negative-coordinate
coordinate:
    number
number:
    sign? integer-constant
    | sign? floating-point-constant
negative-coordinate:
    "-" integer-constant
    | "-" floating-point-constant
comma-wsp:
    (wsp+ comma? wsp*) | (comma wsp*)
comma:
    ","
integer-constant:
    digit-sequence
floating-point-constant:
    fractional-constant exponent?
    | digit-sequence exponent
fractional-constant:
    digit-sequence? "." digit-sequence
    | digit-sequence "."
exponent:
    ( "e" | "E" ) sign? digit-sequence
sign:
    "+" | "-"
digit-sequence:
    digit
    | digit digit-sequence
digit:
    "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
wsp:
    (#x20 | #x9 | #xD | #xA)+

9.8 DOM interfaces

9.8.1 Інтерфейс SVGRectElement

The SVGRectElement interface corresponds to the ‘rect’ елемент.

interface SVGRectElement : SVGElement,
                           SVGTests,
                           SVGLangSpace,
                           SVGExternalResourcesRequired,
                           SVGStylable,
                           SVGTransformable {
  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
  readonly атрибут SVGAnimatedLength width;
  readonly атрибут SVGAnimatedLength height;
  readonly атрибут SVGAnimatedLength rx;
  readonly атрибут SVGAnimatedLength ry;
};

Attributes:

x (readonly SVGAnimatedLength): Corresponds to атрибут ‘x’ on the given ‘rect’ елемент.
y (readonly SVGAnimatedLength): Corresponds to атрибут ‘y’ on the given ‘rect’ елемент.
width (readonly SVGAnimatedLength): Corresponds to атрибут ‘width’ on the given ‘rect’ елемент.
height (readonly SVGAnimatedLength): Corresponds to атрибут ‘height’ on the given ‘rect’ елемент.
rx (readonly SVGAnimatedLength): Corresponds to атрибут ‘rx’ on the given ‘rect’ елемент.
ry (readonly SVGAnimatedLength): Corresponds to атрибут ‘ry’ on the given ‘rect’ елемент.

9.8.2 Інтерфейс SVGCircleElement

The SVGCircleElement interface corresponds to the ‘circle’ елемент.

interface SVGCircleElement : SVGElement,
                             SVGTests,
                             SVGLangSpace,
                             SVGExternalResourcesRequired,
                             SVGStylable,
                             SVGTransformable {
  readonly атрибут SVGAnimatedLength cx;
  readonly атрибут SVGAnimatedLength cy;
  readonly атрибут SVGAnimatedLength r;
};

Attributes:

cx (readonly SVGAnimatedLength): Corresponds to атрибут ‘cx’ on the given ‘circle’ елемент.
cy (readonly SVGAnimatedLength): Corresponds to атрибут ‘cy’ on the given ‘circle’ елемент.
r (readonly SVGAnimatedLength): Corresponds to атрибут ‘r’ on the given ‘circle’ елемент.

9.8.3 Інтерфейс SVGEllipseElement

The SVGEllipseElement interface corresponds to the ‘ellipse’ елемент.

interface SVGEllipseElement : SVGElement,
                              SVGTests,
                              SVGLangSpace,
                              SVGExternalResourcesRequired,
                              SVGStylable,
                              SVGTransformable {
  readonly атрибут SVGAnimatedLength cx;
  readonly атрибут SVGAnimatedLength cy;
  readonly атрибут SVGAnimatedLength rx;
  readonly атрибут SVGAnimatedLength ry;
};

Attributes:

cx (readonly SVGAnimatedLength): Corresponds to атрибут ‘cx’ on the given ‘ellipse’ елемент.
cy (readonly SVGAnimatedLength): Corresponds to атрибут ‘cy’ on the given ‘ellipse’ елемент.
rx (readonly SVGAnimatedLength): Corresponds to атрибут ‘rx’ on the given ‘ellipse’ елемент.
ry (readonly SVGAnimatedLength): Corresponds to атрибут ‘ry’ on the given ‘ellipse’ елемент.

9.8.4 Інтерфейс SVGLineElement

The SVGLineElement interface corresponds to the ‘line’ елемент.

interface SVGLineElement : SVGElement,
                           SVGTests,
                           SVGLangSpace,
                           SVGExternalResourcesRequired,
                           SVGStylable,
                           SVGTransformable {
  readonly атрибут SVGAnimatedLength x1;
  readonly атрибут SVGAnimatedLength y1;
  readonly атрибут SVGAnimatedLength x2;
  readonly атрибут SVGAnimatedLength y2;
};

Attributes:

x1 (readonly SVGAnimatedLength): Corresponds to атрибут ‘x1’ on the given ‘line’ елемент.
y1 (readonly SVGAnimatedLength): Corresponds to атрибут ‘y1’ on the given ‘line’ елемент.
x2 (readonly SVGAnimatedLength): Corresponds to атрибут ‘x2’ on the given ‘line’ елемент.
y2 (readonly SVGAnimatedLength): Corresponds to атрибут ‘y2’ on the given ‘line’ елемент.

9.8.5 Інтерфейс SVGAnimatedPoints

The SVGAnimatedPoints interface supports елементи which have a ‘points’ атрибут which holds a list of coordinate values and which support the ability to animate that атрибут.

Additionally, the ‘points’ атрибут on the original елемент accessed via the XML DOM (e.g., using the getAttribute() method call) will reflect any changes made to points.

interface SVGAnimatedPoints {
  readonly атрибут SVGPointList points;
  readonly атрибут SVGPointList animatedPoints;
};

Attributes:

points (readonly SVGPointList): Provides access to the base (i.e., static) contents of the ‘points’ атрибут.
animatedPoints (readonly SVGPointList): Provides access to the current animated contents of the ‘points’ атрибут. If the given атрибут or властивість is being animated, contains the current animated value of the атрибут or властивість. If the given атрибут or властивість is not currently being animated, contains the same value as points.

9.8.6 Інтерфейс SVGPolylineElement

The SVGPolylineElement interface corresponds to the ‘polyline’ елемент.

interface SVGPolylineElement : SVGElement,
                               SVGTests,
                               SVGLangSpace,
                               SVGExternalResourcesRequired,
                               SVGStylable,
                               SVGTransformable,
                               SVGAnimatedPoints {
};

9.8.7 Інтерфейс SVGPolygonElement

The SVGPolygonElement interface corresponds to the ‘polygon’ елемент.

interface SVGPolygonElement : SVGElement,
                              SVGTests,
                              SVGLangSpace,
                              SVGExternalResourcesRequired,
                              SVGStylable,
                              SVGTransformable,
                              SVGAnimatedPoints {
};

10 Text

10.1 Вступ
10.2 Characters and their corresponding glyphs
10.3 Fonts, font tables and baselines
10.4 The ‘text’ елемент
10.5 The ‘tspan’ елемент
10.6 The ‘tref’ елемент
10.7 Text layout
10.8 Text rendering order
10.9 Alignment властивості
- 10.9.1 Text alignment властивості
- 10.9.2 Baseline alignment властивості
10.10 Font selection властивості
10.11 Spacing властивості
10.12 Text decoration
10.13 Text on a path
10.14 Alternate glyphs
- 10.14.1 The ‘altGlyph’ елемент
- 10.14.2 The ‘altGlyphDef’, ‘altGlyphItem’ and ‘glyphRef’ елементи
10.15 White space handling
10.16 Text selection and clipboard operations
10.17 DOM interfaces

10.1 Вступ

Text that is to be rendered as part of an SVG document fragment is specified using the ‘text’ елемент. The characters to be drawn are expressed as XML character data ([XML10], section 2.4) inside the ‘text’ елемент.

SVG's ‘text’ елементи are rendered like other graphics елементи. Thus, coordinate system transformations, painting, clipping and masking features apply to ‘text’ елементи in the same way as they apply to shapes such as paths and rectangles.

Each ‘text’ елемент causes a single string of text to be rendered. SVG performs no automatic line breaking or word wrapping. To achieve the effect of multiple lines of text, use one of the following methods:

The author or authoring package needs to pre-compute the line breaks and use multiple ‘text’ елементи (one for each line of text).
The author or authoring package needs to pre-compute the line breaks and use a single ‘text’ елемент with one or more ‘tspan’ child елементи with appropriate values for атрибути ‘x’, ‘y’, ‘dx’ and ‘dy’ to set new start positions for those characters which start new lines. (This approach allows user text selection across multiple lines of text -- see Text selection and clipboard operations.)
Express the text to be rendered in another XML namespace such as XHTML [XHTML] embedded inline within a ‘foreignObject’ елемент. (Note: the exact semantics of this approach are not completely defined at this time.)

The text strings within ‘text’ елементи can be rendered in a straight line or rendered along the outline of a ‘path’ елемент. SVG supports the following international text processing features for both straight line text and text on a path:

horizontal and vertical orientation of text
left-to-right or bidirectional text (i.e., languages which intermix right-to-left and left-to-right text, such as Arabic and Hebrew)
when SVG fonts are used, automatic selection of the correct glyph corresponding to the current form for Arabic and Han text

(The layout rules for straight line text are described in Text layout. The layout rules for text on a path are described in Text on a path layout rules.)

Because SVG text is packaged as XML character data:

Text data in SVG content is readily accessible to the visually impaired (see Accessibility Support)
In many viewing scenarios, the user will be able to search for and select text strings and copy selected text strings to the system clipboard (see Text selection and clipboard operations)
XML-compatible Web search engines will find text strings in SVG content with no additional effort over what they need to do to find text strings in other XML documents

Multi-language SVG content is possible by substituting different text strings based on the user's preferred language.

For accessibility reasons, it is recommended that text which is included in a document have appropriate semantic markup to indicate its function. See SVG accessibility guidelines for more information.

10.2 Characters and their corresponding glyphs

In XML [XML10], textual content is defined in terms of a sequence of XML characters, where each character is defined by a particular Unicode code point [UNICODE]. Fonts, on the other hand, consist of a collection of glyphs and other associated information, such as font tables. A glyph is a presentable form of one or more characters (or a part of a character in some cases). Each glyph consists of some sort of identifier (in some cases a string, in other cases a number) along with drawing instructions for rendering that particular glyph.

In many cases, there is a one-to-one mapping of Unicode characters (i.e., Unicode code points) to glyphs in a font. For example, it is common for a font designed for Latin languages (where the term Latin is used for European languages such as English with alphabets similar to and/or derivative to the Latin language) to contain a single glyph for each of the standard ASCII characters (i.e., A-to-Z, a-to-z, 0-to-9, plus the various punctuation characters found in ASCII). Thus, in most situations, the string "XML", which consists of three Unicode characters, would be rendered by the three glyphs corresponding to "X", "M" and "L", respectively.

In various other cases, however, there is not a strict one-to-one mapping of Unicode characters to glyphs. Some of the circumstances when the mapping is not one-to-one:

Ligatures - For best looking typesetting, it is often desirable that particular sequences of characters are rendered as a single glyph. An example is the word "office". Many fonts will define an "ffi" ligature. When the word "office" is rendered, sometimes the user agent will render the glyph for the "ffi" ligature instead of rendering distinct glyphs (i.e., "f", "f" and "i") for each of the three characters. Thus, for ligatures, multiple Unicode characters map to a single glyph. (Note that for proper rendering of some languages, ligatures are required for certain character combinations.)
Composite characters - In various situations, commonly used adornments such as diacritical marks will be stored once in a font as a particular glyph and then composed with one or more other glyphs to result in the desired character. For example, it is possible that a font engine might render the é character by first rendering the glyph for e and then rendering the glyph for ´ (the accent mark) such that the accent mark will appear over the e. In this situation, a single Unicode character maps to multiple glyphs.
Glyph substitution - Some typography systems examine the nature of the textual content and utilize different glyphs in different circumstances. For example, in Arabic, the same Unicode character might render as any of four different glyphs, depending on such factors as whether the character appears at the start, the end or the middle of a sequence of cursively joined characters. Different glyphs might be used for a punctuation character depending on inline-progression-direction (e.g., horizontal vs. vertical). In these situations, a single Unicode character might map to one of several alternative glyphs.
In some languages, particular sequences of characters will be converted into multiple glyphs such that parts of a particular character are in one glyph and the remainder of that character is in another glyph.
Alternative glyph specification - SVG contains a facility for the author to explicitly specify that a particular sequence of Unicode characters is to be rendered using a particular glyph. (See Alternate glyphs.) When this facility is used, multiple Unicode characters map to a single glyph.

In many situations, the algorithms for mapping from characters to glyphs are system-dependent, resulting in the possibility that the rendering of text might be (usually slightly) different when viewed in different user environments. If the author of SVG content requires precise selection of fonts and glyphs, then the recommendation is that the necessary fonts (potentially subsetted to include only the glyphs needed for the given document) be available either as SVG fonts embedded within the SVG content or as WebFonts ([CSS2], section 15.1) posted at the same Web location as the SVG content.

Throughout this chapter, the term character shall be equivalent to the definition of a character in XML [XML10].

10.3 Fonts, font tables and baselines

A font consists of a collection of glyphs together with the information (the font tables) necessary to use those glyphs to present characters on some medium. The combination of the collection of glyphs and the font tables is called the font data. The font tables include the information necessary to map characters to glyphs, to determine the size of glyph areas and to position the glyph area. Each font table consists of one or more font characteristics, such as the font-weight and font-style.

The geometric font characteristics are expressed in a coordinate system based on the EM box. (The EM is a relative measure of the height of the glyphs in the font; see Coordinate units on the em square; in [CSS2], section 15.4.3.) The box 1 EM high and 1 EM wide is called the design space. This space is given a geometric coordinates by sub-dividing the EM into a number of units per em.

Note: Units per em is a font characteristic. A typical value for units per em is 1000 or 2048.

The coordinate space of the EM box is called the design space coordinate system. For scalable fonts, the curves and lines that are used to draw a glyph are represented using this coordinate system.

Note: Most often, the (0,0) point in this coordinate system is positioned on the left edge of the EM box, but not at the bottom left corner. The Y coordinate of the bottom of a roman capital letter is usually zero. And the descenders on lowercase roman letters have negative coordinate values.

SVG assumes that the font tables will provide at least three font characteristics: an ascent, a descent and a set of baseline-tables. The ascent is the distance to the top of the EM box from the (0,0) point of the font; the descent is the distance to the bottom of the EM box from the (0.0) point of the font. The baseline-table is explained below.

Note: Within an OpenType font, for horizontal writing-modes, the ascent and descent are given by the sTypoAscender and sTypoDescender entries in the OS/2 table. For vertical writing-modes, the descent (the distance, in this case from the (0,0) point to the left edge of the glyph) is normally zero because the (0,0) point is on the left edge. The ascent for vertical writing-modes is either 1 em or is specified by the ideographic top baseline value in the OpenType Base table for vertical writing-modes.

In horizontal writing-modes, the glyphs of a given script are positioned so that a particular point on each glyph, the alignment-point, is aligned with the alignment-points of the other glyphs in that script. The glyphs of different scripts, for example, Western, Northern Indic and Far-Eastern scripts, are typically aligned at different points on the glyph. For example, Western glyphs are aligned on the bottoms of the capital letters, northern indic glyphs are aligned at the top of a horizontal stroke near the top of the glyphs and far-eastern glyphs are aligned either at the bottom or center of the glyph. Within a script and within a line of text having a single font-size, the sequence of alignment-points defines, in the inline- progression-direction, a geometric line called a baseline. Western and most other alphabetic and syllabic glyphs are aligned to an "alphabetic" baseline, the northern indic glyphs are aligned to a "hanging" baseline and the far-eastern glyphs are aligned to an "ideographic" baseline.

A baseline-table specifies the position of one or more baselines in the design space coordinate system. The function of the baseline table is to facilitate the alignment of different scripts with respect to each other when they are mixed on the same text line. Because the desired relative alignments may depend on which script is dominant in a line (or block), there may be a different baseline table for each script. In addition, different alignment positions are needed for horizontal and vertical writing modes. Therefore, the font may have a set of baseline tables: typically, one or more for horizontal writing-modes and zero or more for vertical writing-modes.

Note: Some fonts may not have values for the baseline tables. Heuristics are suggested for approximating the baseline tables when a given font does not supply baseline tables.

SVG further assumes that for each glyph in the font data for a font, there are two width values, two alignment-baselines and two alignment-points, one each for horizontal writing-modes and the other for vertical writing-modes. (Even though it is specified as a width, for vertical writing-modes the width is used in the vertical direction.) The script to which a glyph belongs determines an alignment-baseline to which the glyph is to be aligned. The inline-progression-direction position of the alignment-point is on the start-edge of the glyph.

Properties related to baselines are described below under Baseline alignment властивості.

In addition to the font characteristics required above, a font may also supply substitution and positioning tables that can be used by a formatter to re-order, combine and position a sequence of glyphs to make one or more composite glyphs. The combination may be as simple as a ligature, or as complex as an indic syllable which combines, usually with some re-ordering, multiple consonants and vowel glyphs.

10.4 The ‘text’ елемент

The ‘text’ елемент defines a graphics елемент consisting of text. The XML character data within the ‘text’ елемент, along with relevant атрибути and властивості and character-to-glyph mapping tables within the font itself, define the glyphs to be rendered. (See Characters and their corresponding glyphs.) The атрибути and властивості on the ‘text’ елемент indicate such things as the writing direction, font specification and painting атрибути which describe how exactly to render the characters. Subsequent sections of this chapter describe the relevant text-specific атрибути and властивості, particular text layout and bidirectionality.

Since ‘text’ елементи are rendered using the same rendering methods as other graphics елементи, all of the same coordinate system transformations, painting, clipping and masking features that apply to shapes such as paths and rectangles also apply to ‘text’ елементи.

It is possible to apply a gradient, pattern, clipping path, mask or filter to text. When one of these facilities is applied to text and keyword 'objectBoundingBox' is used (see Object bounding box units) to specify a graphical effect relative to the "object bounding box", then the object bounding box units are computed relative to the entire ‘text’ елемент in all cases, even when different effects are applied to different ‘tspan’ елементи within the same ‘text’ елемент.

The ‘text’ елемент renders its first glyph (after bidirectionality reordering) at the initial current text position, which is established by the ‘x’ and ‘y’ атрибути on the ‘text’ елемент (with possible adjustments due to the value of the ‘text-anchor’ властивість, the presence of a ‘textPath’ елемент containing the first character, and/or an ‘x’, ‘y’, ‘dx’ or ‘dy’ атрибути on a ‘tspan’, ‘tref’ or ‘altGlyph’ елемент which contains the first character). After the glyph(s) corresponding to the given character is(are) rendered, the current text position is updated for the next character. In the simplest case, the new current text position is the previous current text position plus the glyphs' advance value (horizontal or vertical). See text layout for a description of glyph placement and glyph advance.

‘text’

Categories:

Graphics елемент, text content елемент

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
text content child елементи — ‘altGlyph’, ‘textPath’, ‘tref’, ‘tspan’
‘a’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘lengthAdjust’
‘x’
‘y’
‘dx’
‘dy’
‘rotate’
‘textLength’

DOM Інтерфейсs:

SVGTextElement

Attribute definitions:

x = "<list-of-coordinates>": If a single <coordinate> is provided, then the value represents the new absolute X coordinate for the current text position for rendering the glyphs that correspond to the first character within this елемент or any of its descendants.
If a comma- or space-separated list of n <coordinate>s is provided, then the values represent new absolute X coordinates for the current text position for rendering the glyphs corresponding to each of the first n characters within this елемент or any of its descendants.
For additional processing rules, refer to the description of the ‘x’ атрибут on the ‘tspan’ елемент.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
y = "<list-of-coordinates>": The corresponding list of absolute Y coordinates for the glyphs corresponding to the characters within this елемент. The processing rules for the ‘y’ атрибут parallel the processing rules for the ‘x’ атрибут.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
dx = "<list-of-lengths>": Shifts in the current text position along the x-axis for the characters within this елемент or any of its descendants.
Refer to the description of the ‘dx’ атрибут on the ‘tspan’ елемент.
If the атрибут is not specified on this елемент or any of its descendants, no supplemental shifts along the x-axis will occur.
Animatable: yes.
dy = "<list-of-lengths>": Shifts in the current text position along the y-axis for the characters within this елемент or any of its descendants.
Refer to the description of the ‘dy’ атрибут on the ‘tspan’ елемент.
If the атрибут is not specified on this елемент or any of its descendants, no supplemental shifts along the y-axis will occur.
Animatable: yes.
rotate = "<list-of-numbers>": The supplemental rotation about the current text position that will be applied to all of the glyphs corresponding to each character within this елемент.
Refer to the description of the ‘rotate’ атрибут on the ‘tspan’ елемент.
If the атрибут is not specified on this елемент or any of its descendants, no supplemental rotations will occur.
Animatable: yes (non-additive).
textLength = "<length>": The author's computation of the total sum of all of the advance values that correspond to character data within this елемент, including the advance value on the glyph (horizontal or vertical), the effect of властивості ‘kerning’, ‘letter-spacing’ and ‘word-spacing’ and adjustments due to атрибути ‘dx’ and ‘dy’ on ‘tspan’ елементи. This value is used to calibrate the user agent's own calculations with that of the author.
The purpose of this атрибут is to allow the author to achieve exact alignment, in visual rendering order after any bidirectional reordering, for the first and last rendered glyphs that correspond to this елемент; thus, for the last rendered character (in visual rendering order after any bidirectional reordering), any supplemental inter-character spacing beyond normal glyph advances are ignored (in most cases) when the user agent determines the appropriate amount to expand/compress the text string to fit within a length of ‘textLength’.
A negative value is an error (see Error processing).
If the атрибут is not specified, the effect is as if the author's computation exactly matched the value calculated by the user agent; thus, no advance adjustments are made.
Animatable: yes.
lengthAdjust = "spacing|spacingAndGlyphs": Indicates the type of adjustments which the user agent shall make to make the rendered length of the text match the value specified on the ‘textLength’ атрибут.
'spacing' indicates that only the advance values are adjusted. The glyphs themselves are not stretched or compressed.
'spacingAndGlyphs' indicates that the advance values are adjusted and the glyphs themselves stretched or compressed in one axis (i.e., a direction parallel to the inline-progression-direction).
The user agent is required to achieve correct start and end positions for the text strings, but the locations of intermediate glyphs are not predictable because user agents might employ advanced algorithms to stretch or compress text strings in order to balance correct start and end positioning with optimal typography.
Note that, for a text string that contains n characters, the adjustments to the advance values often occur only for n−1 characters (see description of атрибут ‘textLength’), whereas stretching or compressing of the glyphs will be applied to all n characters.
If the атрибут is not specified, the effect is as a value of 'spacing' were specified.
Animatable: yes.

Example text01 below contains the text string "Hello, out there" which will be rendered onto the canvas using the Verdana font family with the glyphs filled with the color blue.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 1000 300"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example text01 - 'Hello, out there' in blue</desc>

  <text x="250" y="150" 
        font-family="Verdana" font-size="55" fill="blue" >
    Hello, out there
  </text>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example test01

View this example as SVG (SVG-enabled browsers only)

10.5 The ‘tspan’ елемент

Within a ‘text’ елемент, text and font властивості and the current text position can be adjusted with absolute or relative coordinate values by including a ‘tspan’ елемент.

‘tspan’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’
‘a’
‘altGlyph’
‘animate’
‘animateColor’
‘set’
‘tref’
‘tspan’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘x’
‘y’
‘dx’
‘dy’
‘rotate’
‘textLength’
‘lengthAdjust’

DOM Інтерфейсs:

SVGTSpanElement

Attribute definitions:

x = "<list-of-coordinates>": If a single <coordinate> is provided, then the value represents the new absolute X coordinate for the current text position for rendering the glyphs that correspond to the first character within this елемент or any of its descendants.
If a comma- or space-separated list of n <coordinate>s is provided, then the values represent new absolute X coordinates for the current text position for rendering the glyphs corresponding to each of the first n characters within this елемент or any of its descendants.
If more <coordinate>s are provided than characters, then the extra <coordinate>s will have no effect on glyph positioning.
If more characters exist than <coordinate>s, then for each of these extra characters: (a) if an ancestor ‘text’ or ‘tspan’ елемент specifies an absolute X coordinate for the given character via an ‘x’ атрибут, then that absolute X coordinate is used as the starting X coordinate for that character (nearest ancestor has precedence), else (b) the starting X coordinate for rendering the glyphs corresponding to the given character is the X coordinate of the resulting current text position from the most recently rendered glyph for the current ‘text’ елемент.
If the атрибут is not specified: (a) if an ancestor ‘text’ or ‘tspan’ елемент specifies an absolute X coordinate for a given character via an ‘x’ атрибут, then that absolute X coordinate is used (nearest ancestor has precedence), else (b) the starting X coordinate for rendering the glyphs corresponding to a given character is the X coordinate of the resulting current text position from the most recently rendered glyph for the current ‘text’ елемент.
Animatable: yes.
y = "<list-of-coordinates>": The corresponding list of absolute Y coordinates for the glyphs corresponding to the characters within this елемент. The processing rules for the ‘y’ атрибут parallel the processing rules for the ‘x’ атрибут.
Animatable: yes.
dx = "<list-of-lengths>": If a single <length> is provided, this value represents the new relative X coordinate for the current text position for rendering the glyphs corresponding to the first character within this елемент or any of its descendants. The current text position is shifted along the x-axis of the current user coordinate system by <length> before the first character's glyphs are rendered.
If a comma- or space-separated list of n <length>s is provided, then the values represent incremental shifts along the x-axis for the current text position before rendering the glyphs corresponding to the first n characters within this елемент or any of its descendants. Thus, before the glyphs are rendered corresponding to each character, the current text position resulting from drawing the glyphs for the previous character within the current ‘text’ елемент is shifted along the X axis of the current user coordinate system by <length>.
If more <length>s are provided than characters, then any extra <length>s will have no effect on glyph positioning.
If more characters exist than <length>s, then for each of these extra characters: (a) if an ancestor ‘text’ or ‘tspan’ елемент specifies a relative X coordinate for the given character via a ‘dx’ атрибут, then the current text position is shifted along the x-axis of the current user coordinate system by that amount (nearest ancestor has precedence), else (b) no extra shift along the x-axis occurs.
If the атрибут is not specified: (a) if an ancestor ‘text’ or ‘tspan’ елемент specifies a relative X coordinate for a given character via a ‘dx’ атрибут, then the current text position is shifted along the x-axis of the current user coordinate system by that amount (nearest ancestor has precedence), else (b) no extra shift along the x-axis occurs.
Animatable: yes.
dy = "<list-of-lengths>": The corresponding list of relative Y coordinates for the characters within the ‘tspan’ елемент. The processing rules for the ‘dy’ атрибут parallel the processing rules for the ‘dx’ атрибут.
Animatable: yes.
rotate = "<list-of-numbers>": The supplemental rotation about the current text position that will be applied to all of the glyphs corresponding to each character within this елемент.
If a comma- or space-separated list of <number>s is provided, then the first <number> represents the supplemental rotation for the glyphs corresponding to the first character within this елемент or any of its descendants, the second <number> represents the supplemental rotation for the glyphs that correspond to the second character, and so on.
If more <number>s are provided than there are characters, then the extra <number>s will be ignored.
If more characters are provided than <number>s, then for each of these extra characters the rotation value specified by the last number must be used.
If the атрибут is not specified and if an ancestor ‘text’ or ‘tspan’ елемент specifies a supplemental rotation for a given character via a ‘rotate’ атрибут, then the given supplemental rotation is applied to the given character (nearest ancestor has precedence). If there are more characters than <number>s specified in the ancestor's ‘rotate’ атрибут, then for each of these extra characters the rotation value specified by the last number must be used.
This supplemental rotation has no impact on the rules by which current text position is modified as glyphs get rendered and is supplemental to any rotation due to text on a path and to ‘glyph-orientation-horizontal’ or ‘glyph-orientation-vertical’.
Animatable: yes (non-additive).
textLength = "<length>": The author's computation of the total sum of all of the advance values that correspond to character data within this елемент, including the advance value on the glyph (horizontal or vertical), the effect of властивості ‘kerning’, ‘letter-spacing’ and ‘word-spacing’ and adjustments due to атрибути ‘dx’ and ‘dy’ on this ‘tspan’ елемент or any descendants. This value is used to calibrate the user agent's own calculations with that of the author.
The purpose of this атрибут is to allow the author to achieve exact alignment, in visual rendering order after any bidirectional reordering, for the first and last rendered glyphs that correspond to this елемент; thus, for the last rendered character (in visual rendering order after any bidirectional reordering), any supplemental inter-character spacing beyond normal glyph advances are ignored (in most cases) when the user agent determines the appropriate amount to expand/compress the text string to fit within a length of ‘textLength’.
If атрибут ‘textLength’ is specified on a given елемент and also specified on an ancestor, the adjustments on all character data within this елемент are controlled by the value of ‘textLength’ on this елемент exclusively, with the possible side-effect that the adjustment ratio for the contents of this елемент might be different than the adjustment ratio used for other content that shares the same ancestor. The user agent must assume that the total advance values for the other content within that ancestor is the difference between the advance value on that ancestor and the advance value for this елемент.
A negative value is an error (see Error processing).
If the атрибут is not specified anywhere within a ‘text’ елемент, the effect is as if the author's computation exactly matched the value calculated by the user agent; thus, no advance adjustments are made.
Animatable: yes.

The ‘x’, ‘y’, ‘dx’, ‘dy’ and ‘rotate’ on the ‘tspan’ елемент are useful in high-end typography scenarios where individual glyphs require exact placement. These атрибути are useful for minor positioning adjustments between characters or for major positioning adjustments, such as moving the current text position to a new location to achieve the visual effect of a new line of text. Multi-line ‘text’ елементи are possible by defining different ‘tspan’ елементи for each line of text, with атрибути ‘x’, ‘y’, ‘dx’ and/or ‘dy’ defining the position of each ‘tspan’. (An advantage of such an approach is that users will be able to perform multi-line text selection.)

In situations where micro-level positioning adjustment are necessary for advanced typographic control, the SVG content designer needs to ensure that the necessary font will be available for all viewers of the document (e.g., package up the necessary font data in the form of an SVG font or an alternative WebFont format which is stored at the same Web site as the SVG content) and that the viewing software will process the font in the expected way (the capabilities, characteristics and font layout mechanisms vary greatly from system to system). If the SVG content contains ‘x’, ‘y’, ‘dx’ or ‘dy’ атрибут values which are meant to correspond to a particular font processed by a particular set of viewing software and either of these requirements is not met, then the text might display with poor quality.

The following additional rules apply to атрибути ‘x’, ‘y’, ‘dx’, ‘dy’ and ‘rotate’ when they contain a list of numbers:

When a single XML character maps to a single glyph - In this case, the i-th value for the ‘x’, ‘y’, ‘dx’, ‘dy’ and ‘rotate’ атрибути is applied to the glyph that corresponds to the i-th character.
When a single XML character maps to multiple glyphs (e.g., when an accent glyph is placed on top of a base glyph) - In this case, the i-th value for the ‘x’, ‘y’, ‘dx’ and ‘dy’ values are applied (i.e., the current text position is adjusted) before rendering the first glyph. The rotation transformation corresponding to the i-th ‘rotate’ value is applied to the glyphs and to the inter-glyph advance values corresponding to this character on a group basis (i.e., the rotation value creates a temporary new rotated coordinate system, and the glyphs orresponding to the character are rendered into this rotated coordinate system).
When multiple XML characters map to a single glyph (e.g., when a ligature is used) - Suppose that the i-th and (i+1)-th XML characters map to a single glyph. In this case, the i-th value for the ‘x’, ‘y’, ‘dx’, ‘dy’ and ‘rotate’ атрибути all apply when rendering the glyph. The (i+1)-th values, however, for ‘x’, ‘y’ and ‘rotate’ are ignored (exception: the final ‘rotate’ value in the list would still apply to subsequent characters), whereas the ‘dx’ and ‘dy’ are applied to the subsequent XML character (i.e., the (i+2)-th character), if one exists, by translating the current text position by the given amounts before rendering the first glyph associated with that character.
When there is a many-to-many mapping of characters to glyphs (e.g., when three characters map to two glyphs, such as when the first glyph expresses the first character and half of the second character, and the second glyph expresses the other half of the second character plus the third character) - Suppose that the i-th, (i+1)-th and (i+2)-th XML characters map to two glyphs. In this case, the i-th value for the ‘x’, ‘y’, ‘dx’ and ‘dy’ values are applied (i.e., the current text position is adjusted) before rendering the first glyph. The rotation transformation corresponding to the i-th ‘rotate’ value is applied to both the two glyphs and the glyph advance values for the first glyph on a group basis (i.e., the rotation value creates a temporary new rotated coordinate system, and the two glyphs are rendered into the temporary rotated coordinate system). The (i+1)-th and (i+2)-th values, however, for the ‘x’, ‘y’ and ‘rotate’ атрибути are not applied (exception: the final ‘rotate’ value in the list would still apply to subsequent characters), whereas the (i+1)-th and (i+2)-th values for the ‘dx’ and ‘dy’ атрибути are applied to the subsequent XML character (i.e., the (i+3)-th character), if one exists, by translating the current text position by the given amounts before rendering the first glyph associated with that character.
Relationship to bidirectionality - As described below in the discussion on bidirectionality, text is laid out in a two-step process, where any bidirectional text is first re-ordered into a left-to-right string, and then text layout occurs with the re-ordered text string. Whenever the character data within a ‘tspan’ елемент is re-ordered, the corresponding елементи within the ‘x’, ‘y’, ‘dx’, ‘dy’ and ‘rotate’ are also re-ordered to maintain the correspondence. For example, suppose that you have the following ‘tspan’ елемент:
```
<tspan dx="11 12 13 14 15 0 21 22 23 0 31 32 33 34 35 36">Latin and Hebrew</tspan>
```
and that the word "Hebrew" will be drawn right-to-left. First, the character data and the corresponding values in the ‘dx’ list will be reordered, such that the text string will be "Latin and werbeH" and the list of values for the ‘dx’ атрибут will be "11 12 13 14 15 0 21 22 23 0 36 35 34 33 32 31". After this re-ordering, the glyphs corresponding to the characters will be positioned using standard left-to-right layout rules.

The following examples show basic use of the ‘tspan’ елемент.

Example tspan01 uses a ‘tspan’ елемент to indicate that the word "not" is to use a bold font and have red fill.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 1000 300"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example tspan01 - using tspan to change visual атрибути</desc>

  <g font-family="Verdana" font-size="45" >
    <text x="200" y="150" fill="blue" >
      You are
        <tspan font-weight="bold" fill="red" >not</tspan>
      a banana.
    </text>
  </g>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example tspan01

Example tspan02 uses the ‘dx’ and ‘dy’ атрибути on the ‘tspan’ елемент to adjust the current text position horizontally and vertically for particular text strings within a ‘text’ елемент.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 1000 300"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example tspan02 - using tspan's dx and dy атрибути 
        for incremental positioning adjustments</desc>

  <g font-family="Verdana" font-size="45" >
    <text x="200" y="150" fill="blue" >
      But you
        <tspan dx="2em" dy="-50" font-weight="bold" fill="red" >
          are
        </tspan>
        <tspan dy="100">
           a peach!
        </tspan>
    </text>
  </g>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example tspan02

View this example as SVG (SVG-enabled browsers only)

Example tspan03 uses the ‘x’ and ‘y’ атрибути on the ‘tspan’ елемент to establish a new absolute current text position for each glyph to be rendered. The example shows two lines of text within a single ‘text’ елемент. Because both lines of text are within the same ‘text’ елемент, the user will be able to select through both lines of text and copy the text to the system clipboard in user agents that support text selection and clipboard operations.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 1000 300"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example tspan03 - using tspan's x and y атрибути 
        for multiline text and precise glyph positioning</desc>

  <g font-family="Verdana" font-size="45" >
    <text fill="rgb(255,164,0)" >
      <tspan x="300 350 400 450 500 550 600 650" y="100">
        Cute and
      </tspan>
      <tspan x="375 425 475 525 575" y="200">
         fuzzy
      </tspan>
    </text>
  </g>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example tspan03

View this example as SVG (SVG-enabled browsers only)

Example tspan04 uses the ‘rotate’ атрибут on the ‘tspan’ елемент to rotate the glyphs to be rendered. This example shows a single text string in a ‘tspan’ елемент that contains more characters than the number of values specified in the ‘rotate’ атрибут. In this case the last value specified in the ‘rotate’ атрибут of the ‘tspan’ must be applied to the remaining characters in the string.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 1000 300"
  xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>
    Example tspan04 - The number of rotate values is less than the number of
    characters in the string.
  </desc>
  <text font-family="Verdana" font-size="55" fill="blue" >
    <tspan x="250" y="150" rotate="-30,0,30">
      Hello, out there
    </tspan>
  </text>
  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
  fill="none" stroke="blue" stroke-width="2" />
</svg>

Example tspan04

View this example as SVG (SVG-enabled browsers only)

Example tspan05 specifies the ‘rotate’ атрибут on the ‘text’ елемент and on all but one of the child ‘tspan’ елементи to rotate the glyphs to be rendered. The example demonstrates the propagation of the ‘rotate’ атрибут.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="100%" height="100%" viewBox="0 0 500 120"
  xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>
    Example tspan05 - propagation of rotation values to nested tspan елементи.
  </desc>
  <text id="parent" font-family="Arial, sans-serif" font-size="32" fill="red" x="40" y="40"
    rotate="5,15,25,35,45,55">
    Not

    <tspan id="child1" rotate="-10,-20,-30,-40" fill="orange">
      all characters

      <tspan id="child2" rotate="70,60,50,40,30,20,10" fill="yellow">
        in
        
        <tspan id="child3">
          the
        </tspan>
      </tspan>

      <tspan id="child4" fill="orange" x="40" y="90">
        text
      </tspan>

      have a
    </tspan>

    <tspan id="child5" rotate="-10" fill="blue">
      specified
    </tspan>

    rotation
  </text>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="498" height="118" fill="none"
        stroke="blue" stroke-width="2" />
</svg>

Example tspan05

View this example as SVG (SVG-enabled browsers only)

Rotation of red text inside the ‘text’ елемент:

The ‘rotate’ value will rotate the characters in the text "Not " by 5, 15, 25 and 35 degrees respectively.
A ‘rotate’ value is applied to the space that follows the text "Not", to the space in between the text in the "child1" and "child5" ‘tspan’ елементи, and to the space before the text "rotation".
The next current ‘rotate’ value specified is 45 followed by 55. The current ‘rotate’ value in the ‘text’ елемент is incremented as subsequent characters in the text of the child ‘tspan’ елементи are processed.
The next immediate ‘tspan’ елемент specifies rotate values for the text, hence the current ‘rotate’ value will change to the next value in the list (but is not used) as each character is processed until the last value of 55 degrees is reached.
The last ‘rotate’ value of 55 degrees will be applied to all the characters in the text "rotation".

Rotation of the orange text inside the "child1" ‘tspan’ елемент:

The ‘rotate’ value will rotate the first 4 characters in the text "all characters " by -10, -20, -30 and -40 respectively.
The last ‘rotate’ value of -40 becomes the current ‘rotate’ value and will be applied to all subsequent characters in the ‘tspan’ елемент and to any child ‘tspan’ елементи that do not specify ‘rotate’ values.
The "child4" ‘tspan’ елемент does not specify any ‘rotate’ values and thus uses the current ‘rotate’ of its ancestor ("child1" ‘tspan’ елемент). All the characters in the text "text" specified within the "child4" ‘tspan’ елемент will be rotated by -40 degrees.
The last ‘rotate’ value of -40 degrees will be applied to all the characters in the text "have a".
A ‘rotate’ value is applied to the space in between the text in the "child2" and "child4" ‘tspan’ елементи, and to the space before the text "have a".

Rotation of the yellow text inside the "child2" ‘tspan’ елемент:

The ‘rotate’ value will rotate the characters in the (yellow) text "in " by 70, 60, and 50 degrees respectively.
A ‘rotate’ value is applied to the space that follows the text "in".
There are more ‘rotate’ values specified than characters, thus the additional ‘rotate’ values will be applied to the "child3" ‘tspan’ елемент which does not specified any ‘rotate’ values.
The characters in the text "the" specified within the "child3" ‘tspan’ елемент will be rotated 40, 30 and 20 degrees respectively.

Rotation of the blue text inside the "child5" ‘tspan’ елемент:

The ‘rotate’ value will rotate all the characters in text "specified" by -10 degrees.
Only one ‘rotate’ value is specified and is thus applied to all characters in the ‘tspan’ елемент.

The following diagram illustrates how the rotation values propagate to ‘tspan’ елементи nested withing a ‘text’ елемент

Image that shows propagation of rotation values

10.6 The ‘tref’ елемент

The textual content for a ‘text’ can be either character data directly embedded within the ‘text’ елемент or the character data content of a referenced елемент, where the referencing is specified with a ‘tref’ елемент.

‘tref’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’
‘animate’
‘animateColor’
‘set’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘xlink:href’

DOM Інтерфейсs:

SVGTRefElement

Attribute definitions:

xlink:href = "<iri>": An IRI reference to an елемент whose character data content shall be used as character data for this ‘tref’ елемент.
Animatable: yes.

All character data within the referenced елемент, including character data enclosed within additional markup, will be rendered.

The ‘x’, ‘y’, ‘dx’, ‘dy’ and ‘rotate’ атрибути have the same meanings as for the ‘tspan’ елемент. The атрибути are applied as if the ‘tref’ елемент was replaced by a ‘tspan’ with the referenced character data (stripped of all supplemental markup) embedded within the hypothetical ‘tspan’ елемент.

Example tref01 shows how to use character data from a different елемент as the character data for a given ‘tspan’ елемент. The first ‘text’ елемент (with id="ReferencedText") will not draw because it is part of a ‘defs’ елемент. The second ‘text’ елемент draws the string "Inline character data". The third ‘text’ елемент draws the string "Reference character data" because it includes a ‘tref’ елемент which is a reference to елемент "ReferencedText", and that елемент's character data is "Referenced character data".

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="10cm" height="3cm" viewBox="0 0 1000 300" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <defs>
    <text id="ReferencedText">
      Referenced character data
    </text>
  </defs>
  <desc>Example tref01 - inline vs reference text content</desc>

  <text x="100" y="100" font-size="45" fill="blue" >
    Inline character data
  </text>
  <text x="100" y="200" font-size="45" fill="red" >
    <tref xlink:href="#ReferencedText"/>
  </text>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example tref01

10.7 Text layout

10.7.1 Text layout introduction

This section describes the text layout features supported by SVG, which includes support for various international writing directions, such as left-to-right (e.g., Latin scripts) and bidirectional (e.g., Hebrew or Arabic) and vertical (e.g., Asian scripts). The descriptions in this section assume straight line text (i.e., text that is either strictly horizontal or vertical with respect to the current user coordinate system). Subsequent sections describe the supplemental layout rules for text on a path.

SVG does not provide for automatic line breaks or word wrapping, which makes internationalized text layout for SVG relatively simpler than it is for languages which support formatting of multi-line text blocks.

For each ‘text’ елемент, the SVG user agent determines the current reference orientation. For standard horizontal or vertical text (i.e., no text-on-a-path), the reference orientation is the vector pointing towards negative infinity in Y within the current user coordinate system. (Note: in the initial coordinate system, the reference orientation is up.) For text on a path, the reference orientation is reset with each character.

Based on the reference orientation and the value for властивість ‘writing-mode’, the SVG user agent determines the current inline-progression-direction. For left-to-right text, the inline-progression-direction points 90 degrees clockwise from the reference orientation vector. For right-to-left text, the inline progression points 90 degrees counter-clockwise from the reference orientation vector. For top-to-bottom text, the inline-progression-direction points 180 degrees from the reference orientation vector.

Based on the reference orientation and the value for властивість ‘writing-mode’, the SVG user agent determines the current block-progression-direction. For left-to-right and right-to-left text, the block-progression-direction points 180 degrees from the reference orientation vector because the only available horizontal ‘writing-mode’s are lr-tb and rl-tb. For top-to-bottom text, the block-progression-direction always points 90 degrees counter-clockwise from the reference orientation vector because the only available top-to-bottom ‘writing-mode’ is tb-rl.

The shift direction is the direction towards which the baseline table moves due to positive values for властивість ‘baseline-shift’. The shift direction is such that a positive value shifts the baseline table towards the topmost entry in the parent's baseline table.

In processing a given ‘text’ елемент, the SVG user agent keeps track of the current text position. The initial current text position is established by the ‘x’ and ‘y’ атрибути on the ‘text’ елемент.

The current text position is adjusted after each glyph to establish a new current text position at which the next glyph shall be rendered. The adjustment to the current text position is based on the current inline-progression-direction, glyph-specific advance values corresponding to the glyph orientation of the glyph just rendered, kerning tables in the font and the current values of various атрибути and властивості, such as the spacing властивості and any ‘x’, ‘y’, ‘dx’ and ‘dy’ атрибути on ‘text’, ‘tspan’, ‘tref’ or ‘altGlyph’ елементи. If a glyph does not provide explicit advance values corresponding to the current glyph orientation, then an appropriate approximation should be used. For vertical text, a suggested approximation is the sum of the ascent and descent values for the glyph. Another suggested approximation for an advance value for both horizontal and vertical text is the size of an em (see units-per-em).

For each glyph to be rendered, the SVG user agent determines an appropriate alignment-point on the glyph which will be placed exactly at the current text position. The alignment-point is determined based on glyph cell metrics in the glyph itself, the current inline-progression-direction and the glyph orientation relative to the inline-progression-direction. For most uses of Latin text (i.e., writing-mode:lr, text-anchor:start and alignment-baseline:baseline) the alignment-point in the glyph will be the intersection of left edge of the glyph cell (or some other glyph-specific x-axis coordinate indicating a left-side origin point) with the Latin baseline of the glyph. For many cases with top-to-bottom vertical text layout, the reference point will be either a glyph-specific origin point based on the set of vertical baselines for the font or the intersection of the center of the glyph with its top line (see Top Baseline; in [CSS2], section 15.4.18). If a glyph does not provide explicit origin points corresponding to the current glyph orientation, then an appropriate approximation should be used, such as the intersection of the left edge of the glyph with the appropriate horizontal baseline for the glyph or intersection of the top edge of the glyph with the appropriate vertical baseline. If baseline tables are not available, user agents should establish baseline tables that reflect common practice.

Adjustments to the current text position are either absolute position adjustments or relative position adjustments. An absolute position adjustment occurs in the following circumstances:

At the start of a ‘text’ елемент
At the start of each ‘textPath’ елемент
For each character within a ‘text’, ‘tspan’, ‘tref’ and ‘altGlyph’ елемент which has an ‘x’ or ‘y’ атрибут value assigned to it explicitly

All other position adjustments to the current text position are relative position adjustments.

Each absolute position adjustment defines a new text chunk. Absolute position adjustments impact text layout in the following ways:

Ligatures only occur when a set of characters which might map to a ligature are all in the same text chunk.
Each text chunk represents a separate block of text for alignment due to ‘text-anchor’ властивість values.
Reordering of characters due to bidirectionality only occurs within a text chunk. Reordering does not happen across text chunks.

The following additional rules apply to ligature formation:

As defined in CSS2, ([CSS2], section 16.4), when the resultant space between two characters is not the same as the default space, user agents should not use ligatures; thus, if there are non-default values for властивості ‘kerning’ or ‘letter-spacing’, the user agent should not use ligatures.
Ligature formation should not be enabled for the glyphs corresponding to characters within different DOM text nodes; thus, characters separated by markup should not use ligatures.
As mentioned above, ligature formation should not be enabled for the glyphs corresponding to characters within different text chunks.

10.7.2 Setting the inline-progression-direction

The ‘writing-mode’ властивість specifies whether the initial inline-progression-direction for a ‘text’ елемент shall be left-to-right, right-to-left, or top-to-bottom. The ‘writing-mode’ властивість applies only to ‘text’ елементи; the властивість is ignored for ‘tspan’, ‘tref’, ‘altGlyph’ and ‘textPath’ sub-елементи. (Note that the inline-progression-direction can change within a ‘text’ елемент due to the Unicode bidirectional algorithm and властивості ‘direction’ and ‘unicode-bidi’. For more on bidirectional text, see Relationship with bidirectionality.)

‘writing-mode’

Value:	lr-tb \| rl-tb \| tb-rl \| lr \| rl \| tb \| inherit
Initial:	lr-tb
Applies to:	‘text’ елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	no

lr-tb | lr: Sets the initial inline-progression-direction to left-to-right, as is common in most Latin-based documents. For most characters, the current text position is advanced from left to right after each glyph is rendered. (When the character data includes characters which are subject to the Unicode bidirectional algorithm, the text advance rules are more complex. See Relationship with bidirectionality).
rl-tb | rl: Sets the initial inline-progression-direction to right-to-left, as is common in Arabic or Hebrew scripts. (See Relationship with bidirectionality.)
tb-rl | tb: Sets the initial inline-progression-direction to top-to-bottom, as is common in some Asian scripts, such as Chinese and Japanese. Though hardly as frequent as horizontal, this type of vertical layout also occurs in Latin based documents, particularly in table column or row labels. In most cases, the vertical baselines running through the middle of each glyph are aligned.

10.7.3 Glyph orientation within a text run

In some cases, it is required to alter the orientation of a sequence of characters relative to the inline-progression-direction. The requirement is particularly applicable to vertical layouts of East Asian documents, where sometimes narrow-cell Latin text is to be displayed horizontally and other times vertically.

Two властивості control the glyph orientation relative to the reference orientation for each of the two possible inline-progression-directions. ‘glyph-orientation-vertical’ controls glyph orientation when the inline-progression-direction is vertical. ‘glyph-orientation-horizontal’ controls glyph orientation when the inline-progression-direction is horizontal.

‘glyph-orientation-vertical’

Value:	auto \| <angle> \| inherit
Initial:	auto
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	no

auto

Fullwidth ideographic and fullwidth Latin text will be set with a glyph-orientation of 0-degrees.

Ideographic punctuation and other ideographic characters having alternate horizontal and vertical forms will use the vertical form of the glyph.
Text which is not fullwidth will be set with a glyph-orientation of 90-degrees.

This reorientation rule applies only to the first-level non-ideographic text. All further embedding of writing-modes or bidi processing will be based on the first-level rotation.
NOTE:
- This is equivalent to having set the non-ideographic text string horizontally honoring the bidi-rule, then rotating the resultant sequence of inline-areas (one area for each change of glyph direction) 90-degrees clockwise.
  
  It should be noted that text set in this "rotated" manner may contain ligatures or other glyph combining and reordering common to the language and script. (This "rotated" presentation form does not disable auto-ligature formation or similar context-driven variations.)
- The determination of which characters should be auto-rotated may vary across user agents. The determination is based on a complex interaction between country, language, script, character властивості, font, and character context. It is suggested that one consult the Unicode TR 11 and the various JIS or other national standards.

<angle>

The value of the angle is restricted to 0, 90, 180, and 270 degrees. The user agent shall round the value of the angle to the closest of the permitted values.
A value of 0deg indicates that all glyphs are set with the top of the glyphs oriented towards the reference orientation. A value of 90deg indicates an orientation of 90 degrees clockwise from the reference orientation.

This властивість is applied only to text written in a vertical ‘writing-mode’.

The glyph orientation affects the amount that the current text position advances as each glyph is rendered. When the inline-progression-direction is vertical and the ‘glyph-orientation-vertical’ results in an orientation angle that is a multiple of 180 degrees, then the current text position is incremented according to the vertical metrics of the glyph. Otherwise, if the ‘glyph-orientation-vertical’ results in an orientation angle that is not a multiple of 180 degrees, then the current text position is incremented according to the horizontal metrics of the glyph.

The text layout diagrams in this section use the following symbols:

	wide-cell glyph (e.g. Han) which is the n-th glyph in the text run
	narrow-cell glyph (e.g. Latin) which is the n-th glyph in the text run

The orientation which the above symbols assume in the diagrams corresponds to the orientation that the Unicode characters they represent are intended to assume when rendered in the user agent. Spacing between the glyphs in the diagrams is usually symbolic, unless intentionally changed to make a point.

The diagrams below illustrate different uses of ‘glyph-orientation-vertical’. The diagram on the left shows the result of the mixing of full-width ideographic glyphs with narrow-cell Latin glyphs when ‘glyph-orientation-vertical’ for the Latin characters is either auto or 90. The diagram on the right show the result of mixing full-width ideographic glyphs with narrow-cell Latin glyphs when Latin glyphs are specified to have a ‘glyph-orientation-vertical’ of 0.

‘glyph-orientation-horizontal’

Value:	<angle> \| inherit
Initial:	0deg
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	no

<angle>: The value of the angle is restricted to 0, 90, 180, and 270 degrees. The user agent shall round the value of the angle to the closest of the permitted values.
A value of 0deg indicates that all glyphs are set with the top of the glyphs oriented towards the reference orientation. A value of 90deg indicates an orientation of 90 degrees clockwise from the reference orientation.

This властивість is applied only to text written in a horizontal ‘writing-mode’.

The glyph orientation affects the amount that the current text position advances as each glyph is rendered. When the reference orientation direction is horizontal and the ‘glyph-orientation-horizontal’ results in an orientation angle that is a multiple of 180 degrees, then the current text position is incremented according to the horizontal metrics of the glyph. Otherwise, if the ‘glyph-orientation-horizontal’ results in an orientation angle that is not a multiple of 180 degrees, then the current text position is incremented according to the vertical metrics of the glyph.

10.7.4 Relationship with bidirectionality

The characters in certain scripts are written from right to left. In some documents, in particular those written with the Arabic or Hebrew script, and in some mixed-language contexts, text in a single line may appear with mixed directionality. This phenomenon is called bidirectionality, or "bidi" for short.

The Unicode standard ([UNICODE], specifically [UAX9]) defines a complex algorithm for determining the proper directionality of text. The algorithm consists of an implicit part based on character властивості, as well as explicit controls for embeddings and overrides. The SVG user agent applies this bidirectional algorithm when determining the layout of characters within a text content block елемент.

The ‘direction’ and ‘unicode-bidi’ властивості allow authors to override the inherent directionality of the content characters and thus explicitly control how the елементи and атрибути of a document language map to this algorithm. These two властивості are applicable to all characters whose glyphs are perpendicular to the inline-progression-direction.

In many cases, the bidirectional algorithm from Unicode [UNICODE] produces the desired result automatically, and in such cases the author does not need to use these властивості. For other cases, such as when using right-to-left languages, it may be sufficient to add the ‘direction’ властивість to the rootmost ‘svg’ елемент, and allow that direction to inherit to all text елементи, as in the following example (which may be used as a template):

<svg xmlns="http://www.w3.org/2000/svg"
     width="100%" height="100%" viewBox="0 0 400 400"
     direction="rtl" xml:lang="fa">

  <title direction="ltr" xml:lang="en">Right-to-left Text</title>
  <desc direction="ltr" xml:lang="en">
    A simple example for using the 'direction' властивість in documents
    that predominantly use right-to-left languages.
  </desc>

  <text x="200" y="200" font-size="20">داستان SVG 1.1 SE طولا ني است.</text>

</svg>

Example

View this example as SVG (SVG-enabled browsers only)

Below is another example, where where implicit bidi reordering is not sufficient:

<?xml version="1.0" encoding="utf-8"?>
<svg xmlns="http://www.w3.org/2000/svg"
     width="100%" height="100%" viewBox="0 0 400 400"
     direction="rtl" xml:lang="he">

  <title direction="ltr" xml:lang="en">Right-to-left Text</title>
  <desc direction="ltr" xml:lang="en">
    An example for using the 'direction' and 'unicode-bidi' властивості
    in documents that predominantly use right-to-left languages.
  </desc>

  <text x="200" y="200" font-size="20"> כתובת 
	MAC:&#x200F;
    	<tspan direction="ltr" unicode-bidi="embed">00-24-AF-2A-55-FC</tspan> 
	</text>

</svg>

Example

View this example as SVG (SVG-enabled browsers only)

Within text content елементи, the alignment of text with regards to the ‘text-anchor’ властивість is determined by the value of the ‘direction’ властивість. For example, given a ‘text’ елемент with a ‘text-anchor’ value of "end", for a ‘direction’ value of "ltr", the text will extend to the left of the position of the ‘text’ елемент's ‘x’ атрибут value, while for ‘direction’ value of "rtl", the text will extend to the right of the position of the ‘text’ елемент's ‘x’ атрибут value.

A more complete discussion of bidirectionality can be found in the Text direction section of CSS 2 ([CSS2], section 9.10).

The processing модель for bidirectional text is as follows. The user agent processes the characters which are provided in logical order (i.e., the order the characters appear in the original document, either via direct inclusion or via indirect reference due a ‘tref’ елемент). The user agent determines the set of independent blocks within each of which it should apply the Unicode bidirectional algorithm. Each text chunk represents an independent block of text. Additionally, any change in glyph orientation due to processing of властивості ‘glyph-orientation-horizontal’ or ‘glyph-orientation-vertical’ will subdivide the independent blocks of text further. After processing the Unicode bidirectional algorithm and властивості ‘direction’ and ‘unicode-bidi’ on each of the independent text blocks, the user agent will have a potentially re-ordered list of characters which are now in left-to-right rendering order. Simultaneous with re-ordering of the characters, the dx, dy and rotate атрибути on the ‘tspan’ and ‘tref’ елементи are also re-ordered to maintain the original correspondence between characters and атрибут values. While kerning or ligature processing might be font-specific, the preferred модель is that kerning and ligature processing occurs between combinations of characters or glyphs after the characters have been re-ordered.

‘direction’

Value:	ltr \| rtl \| inherit
Initial:	ltr
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	no

This властивість specifies the base writing direction of text and the direction of embeddings and overrides (see ‘unicode-bidi’) for the Unicode bidirectional algorithm. For the ‘direction’ властивість to have any effect on an елемент that does not by itself establish a new text chunk (such as a ‘tspan’ елемент without absolute position adjustments due to ‘x’ or ‘y’ атрибути), the ‘unicode-bidi’ властивість's value must be embed or bidi-override.

Except for any additional information provided in this specification, the normative definition of the ‘direction’ властивість is in CSS2 ([CSS2], section 9.10).

The ‘direction’ властивість applies only to glyphs oriented perpendicular to the inline-progression-direction, which includes the usual case of horizontally-oriented Latin or Arabic text and the case of narrow-cell Latin or Arabic characters rotated 90 degrees clockwise relative to a top-to-bottom inline-progression-direction.

‘unicode-bidi’

Value:	normal \| embed \| bidi-override \| inherit
Initial:	normal
Applies to:	text content елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	no

Except for any additional information provided in this specification, the normative definition of the ‘unicode-bidi’ властивість is in CSS2 ([CSS2], section 9.10).

10.8 Text rendering order

The glyphs associated with the characters within a ‘text’ елемент are rendered in the logical order of the characters in the original document, independent of any re-ordering necessary to implement bidirectionality. Thus, for text that goes right-to-left visually, the glyphs associated with the rightmost character are rendered before the glyphs associated with the other characters.

Additionally, each distinct glyph is rendered in its entirety (i.e., it is filled and stroked as specified by the ‘fill’ and ‘stroke’ властивості) before the next glyph gets rendered.

10.9 Alignment властивості

10.9.1 Text alignment властивості

The ‘text-anchor’ властивість is used to align (start-, middle- or end-alignment) a string of text relative to a given point.

The ‘text-anchor’ властивість is applied to each individual text chunk within a given ‘text’ елемент. Each text chunk has an initial current text position, which represents the point in the user coordinate system resulting from (depending on context) application of the ‘x’ and ‘y’ атрибути on the ‘text’ елемент, any ‘x’ or ‘y’ атрибут values on a ‘tspan’, ‘tref’ or ‘altGlyph’ елемент assigned explicitly to the first rendered character in a text chunk, or determination of the initial current text position for a ‘textPath’ елемент.

‘text-anchor’

Value:	start \| middle \| end \| inherit
Initial:	start
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

Values have the following meanings:

start: The rendered characters are aligned such that the start of the resulting rendered text is at the initial current text position. For an елемент with a ‘direction’ властивість value of "ltr" (typical for most European languages), the left side of the text is rendered at the initial text position. For an елемент with a ‘direction’ властивість value of "rtl" (typical for Arabic and Hebrew), the right side of the text is rendered at the initial text position. For an елемент with a vertical primary text direction (often typical for Asian text), the top side of the text is rendered at the initial text position.
middle: The rendered characters are aligned such that the geometric middle of the resulting rendered text is at the initial current text position.
end: The rendered characters are aligned such that the end of the resulting rendered text is at the initial current text position. For an елемент with a ‘direction’ властивість value of "ltr" (typical for most European languages), the right side of the text is rendered at the initial text position. For an елемент with a ‘direction’ властивість value of "rtl" (typical for Arabic and Hebrew), the left side of the text is rendered at the initial text position. For an елемент with a vertical primary text direction (often typical for Asian text), the bottom of the text is rendered at the initial text position.

10.9.2 Baseline alignment властивості

An overview of baseline alignment and baseline tables can be found above in Fonts, font tables and baselines.

One of the characteristics of international text is that there are different baselines (different alignment points) for glyphs in different scripts. For example, in horizontal writing, ideographic scripts, such as Han Ideographs, Katakana, Hiragana, and Hangul, alignment occurs with a baseline near the bottoms of the glyphs; alphabetic based scripts, such as Latin, Cyrillic, Hebrew, Arabic, align a point that is the bottom of most glyphs, but some glyphs descend below the baseline; and Indic based scripts are aligned at a point that is near the top of the glyphs.

When different scripts are mixed on a line of text, an adjustment must be made to ensure that the glyphs in the different scripts are aligned correctly with one another. OpenType [OPENTYPE] fonts have a Baseline table (BASE) [OPENTYPE-BASETABLE] that specifies the offsets of the alternative baselines from the current baseline.

SVG uses a similar baseline table модель that assumes one script (at one font-size) is the "dominant run" during processing of a ‘text’ елемент; that is, all other baselines are defined in relation to this dominant run. The baseline of the script with the dominant run is called the dominant baseline. So, for example, if the dominant baseline is the alphabetic baseline, there will be offsets in the baseline table for the alternate baselines, such as the ideographic baseline and the Indic baseline. There will also be an offset for the math baseline which is used for some math fonts. Note that there are separate baseline tables for horizontal and vertical writing-modes. The offsets in these tables may be different for horizontal and vertical writing.

The baseline table established at the start of processing of a ‘text’ елемент is called the dominant baseline table.

Because the value of the ‘font-family’ властивість is a list of fonts, to insure a consistent choice of baseline table we define the nominal font in a font list as the first font in the list for which a glyph is available. This is the first font that could contain a glyph for each character encountered. (For this definition, glyph data is assumed to be present if a font substitution is made or if the font is synthesized.) This definition insures a content independent determination of the font and baseline table that is to be used.

The value of the ‘font-size’ властивість on the ‘text’ елемент establishes the dominant baseline table font size.

The модель assumes that each glyph has a 'alignment-baseline' value which specifies the baseline with which the glyph is to be aligned. (The 'alignment-baseline' is called the "Baseline Tag" in the OpenType baseline table description.) The initial value of the ‘alignment-baseline’ властивість uses the baseline identifier associated with the given glyph. Alternate values for ‘alignment-baseline’ can be useful for glyphs such as a "*" which are ambiguous with respect to script membership.

The модель assumes that the font from which the glyph is drawn also has a baseline table, the font baseline table. This baseline table has offsets in units-per-em from the (0,0) point to each of the baselines the font knows about. In particular, it has the offset from the glyph's (0,0) point to the baseline identified by the 'alignment-baseline'.

The offset values in the baseline table are in "design units" which means fractional units of the EM. CSS calls these "units-per-em" ([CSS2], section 15.3.4). Thus, the current ‘font-size’ is used to determine the actual offset from the dominant baseline to the alternate baselines.

The glyph is aligned so that its baseline identified by its 'alignment-baseline' is aligned with the baseline with the same name from the dominant baseline table.

The offset from the dominant baseline of the parent to the baseline identified by the 'alignment-baseline' is computed using the dominant baseline table and dominant baseline table font size. The font baseline table and font size applicable to the glyph are used to compute the offset from the identified baseline to the (0,0) point of the glyph. This second offset is subtracted from the first offset to get the position of the (0,0) point in the shift direction. Both offsets are computed by multiplying the baseline value from the baseline table times the appropriate font size value.

If the 'alignment-baseline' identifies the dominant baseline, then the first offset is zero and the glyph is aligned with the dominant baseline; otherwise, the glyph is aligned with the chosen alternate baseline.

The baseline-identifiers below are used in this specification. Some of these are determined by baseline-tables contained in a font as described in XSL ([XSL], section 7.9.1). Others are computed from other font characteristics as described below.

alphabetic: This identifies the baseline used by most alphabetic and syllabic scripts. These include, but are not limited to, many Western, Southern Indic, Southeast Asian (non-ideographic) scripts.
ideographic: This identifies the baseline used by ideographic scripts. For historical reasons, this baseline is at the bottom of the ideographic EM box and not in the center of the ideographic EM box. See the "central" baseline. The ideographic scripts include Chinese, Japanese, Korean, and Vietnamese Chu Nom.
hanging: This identifies the baseline used by certain Indic scripts. These scripts include Devanagari, Gurmukhi and Bengali.
mathematical: This identifies the baseline used by mathematical symbols.
central: This identifies a computed baseline that is at the center of the EM box. This baseline lies halfway between the text-before-edge and text-after-edge baselines.

NOTE:
For ideographic fonts, this baseline is often used to align the glyphs; it is an alternative to the ideographic baseline.
middle: This identifies a baseline that is offset from the alphabetic baseline in the shift-direction by 1/2 the value of the x-height font characteristic. The position of this baseline may be obtained from the font data or, for fonts that have a font characteristic for "x-height", it may be computed using 1/2 the "x-height". Lacking either of these pieces of information, the position of this baseline may be approximated by the "central" baseline.
text-before-edge: This identifies the before-edge of the EM box. The position of this baseline may be specified in the baseline-table or it may be calculated.

NOTE:
The position of this baseline is normally around or at the top of the ascenders, but it may not encompass all accents that can appear above a glyph. For these fonts the value of the "ascent" font characteristic is used. For ideographic fonts, the position of this baseline is normally 1 EM in the shift-direction from the "ideographic" baseline. Якever, some ideographic fonts have a reduced width in the inline-progression-direction to allow tighter setting. When such a font, designed only for vertical writing-modes, is used in a horizontal writing-mode, the "text-before-edge" baseline may be less than 1 EM from the text-after-edge.
text-after-edge: This identifies the after-edge of the EM box. The position of this baseline may be specified in the baseline-table or it may be calculated.

NOTE:
For fonts with descenders, the position of this baseline is normally around or at the bottom of the descenders. For these fonts the value of the "descent" font characteristic is used. For ideographic fonts, the position of this baseline is normally at the "ideographic" baseline.

There are, in addition, two computed baselines that are only defined for line areas. Since SVG does not support the notion of computations based on line areas, the two computed baselines are mapped as follows:

before-edge: For SVG, this is equivalent to text-before-edge.
after-edge: For SVG, this is equivalent to text-after-edge.

There are also four baselines that are defined only for horizontal writing-modes.

top: This baseline is the same as the "before-edge" baseline in a horizontal writing-mode and is undefined in a vertical writing mode.
text-top: This baseline is the same as the "text-before-edge" baseline in a horizontal writing-mode and is undefined in a vertical writing mode.
bottom: This baseline is the same as the "after-edge" baseline in a horizontal writing-mode and is undefined in a vertical writing mode.
text-bottom: This baseline is the same as the "text-after-edge" baseline in a horizontal writing-mode and is undefined in a vertical writing mode.

The baseline-alignment властивості follow.

‘dominant-baseline’

Value:	auto \| use-script \| no-change \| reset-size \| ideographic \| alphabetic \| hanging \| mathematical \| central \| middle \| text-after-edge \| text-before-edge \| inherit
Initial:	auto
Applies to:	text content елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

The "dominant-baseline" властивість is used to determine or re-determine a scaled-baseline-table. A scaled-baseline-table is a compound value with three components: a baseline-identifier for the dominant-baseline, a baseline-table and a baseline-table font-size. Some values of the властивість re-determine all three values; other only re-establish the baseline-table font-size. When the initial value, auto, would give an undesired result, this властивість can be used to explicitly set the desire scaled-baseline-table.

Values for the властивість have the following meaning:

auto

If this властивість occurs on a ‘text’ елемент, then the computed value depends on the value of the ‘writing-mode’ властивість. If the 'writing-mode' is horizontal, then the value of the dominant-baseline component is 'alphabetic', else if the 'writing-mode' is vertical, then the value of the dominant-baseline component is 'central'.

If this властивість occurs on a ‘tspan’, ‘tref’, ‘altGlyph’ or ‘textPath’ елемент, then the dominant-baseline and the baseline-table components remain the same as those of the parent text content елемент. If the computed ‘baseline-shift’ value actually shifts the baseline, then the baseline-table font-size component is set to the value of the ‘font-size’ властивість on the елемент on which the ‘dominant-baseline’ властивість occurs, otherwise the baseline-table font-size remains the same as that of the елемент. If there is no parent text content елемент, the scaled-baseline-table value is constructed as above for ‘text’ елементи.

use-script

The dominant-baseline and the baseline-table components are set by determining the predominant script of the character data content. The ‘writing-mode’, whether horizontal or vertical, is used to select the appropriate set of baseline-tables and the dominant baseline is used to select the baseline-table that corresponds to that baseline. The baseline-table font-size component is set to the value of the ‘font-size’ властивість on the елемент on which the ‘dominant-baseline’ властивість occurs.

no-change

The dominant-baseline, the baseline-table, and the baseline-table font-size remain the same as that of the parent text content елемент.

reset-size

The dominant-baseline and the baseline-table remain the same, but the baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент. This re-scales the baseline-table for the current ‘font-size’.

ideographic

The baseline-identifier for the dominant-baseline is set to be 'ideographic', the derived baseline-table is constructed using the 'ideographic' baseline-table in the nominal font, and the baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент.

alphabetic

The baseline-identifier for the dominant-baseline is set to be 'alphabetic', the derived baseline-table is constructed using the 'alphabetic' baseline-table in the nominal font, and the baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент.

hanging

The baseline-identifier for the dominant-baseline is set to be 'hanging', the derived baseline-table is constructed using the 'hanging' baseline-table in the nominal font, and the baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент.

mathematical

The baseline-identifier for the dominant-baseline is set to be 'mathematical', the derived baseline-table is constructed using the 'mathematical' baseline-table in the nominal font, and the baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент.

central

The baseline-identifier for the dominant-baseline is set to be 'central'. The derived baseline-table is constructed from the defined baselines in a baseline-table in the nominal font. That font baseline-table is chosen using the following priority order of baseline-table names: 'ideographic', 'alphabetic', 'hanging', 'mathematical'. The baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент.

middle

The baseline-identifier for the dominant-baseline is set to be 'middle'. The derived baseline-table is constructed from the defined baselines in a baseline-table in the nominal font. That font baseline -table is chosen using the following priority order of baseline-table names: 'alphabetic', 'ideographic', 'hanging', 'mathematical'. The baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент.

text-after-edge

The baseline-identifier for the dominant-baseline is set to be 'text-after-edge'. The derived baseline-table is constructed from the defined baselines in a baseline-table in the nominal font. The choice of which font baseline-table to use from the baseline-tables in the nominal font is implementation defined. The baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент.

NOTE: using the following priority order of baseline-table names: 'alphabetic', 'ideographic', 'hanging', 'mathematical' is probably a reasonable strategy for determining which font baseline-table to use.

text-before-edge

The baseline-identifier for the dominant-baseline is set to be 'text-before-edge'. The derived baseline-table is constructed from the defined baselines in a baseline-table in the nominal font. The choice of which baseline-table to use from the baseline-tables in the nominal font is implementation defined. The baseline-table font-size is changed to the value of the ‘font-size’ властивість on this елемент.

NOTE: Using the following priority order of baseline-table names: 'alphabetic', 'ideographic', 'hanging', 'mathematical' is probably a reasonable strategy for determining which font baseline-table to use.

If there is no baseline table in the nominal font or if the baseline table lacks an entry for the desired baseline, then the user agent may use heuristics to determine the position of the desired baseline.

‘alignment-baseline’

Value:	auto \| baseline \| before-edge \| text-before-edge \| middle \| central \| after-edge \| text-after-edge \| ideographic \| alphabetic \| hanging \| mathematical \| inherit
Initial:	auto
Applies to:	‘tspan’, ‘tref’, ‘altGlyph’, ‘textPath’ елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість specifies how an object is aligned with respect to its parent. This властивість specifies which baseline of this елемент is to be aligned with the corresponding baseline of the parent. For example, this allows alphabetic baselines in Roman text to stay aligned across font size changes. It defaults to the baseline with the same name as the computed value of the alignment-baseline властивість. That is, the position of "ideographic" alignment-point in the block-progression-direction is the position of the "ideographic" baseline in the baseline-table of the object being aligned.

Values have the following meanings:

auto: The value is the dominant-baseline of the script to which the character belongs - i.e., use the dominant-baseline of the parent.
baseline: The alignment-point of the object being aligned is aligned with the dominant-baseline of the parent text content елемент.
before-edge: The alignment-point of the object being aligned is aligned with the "before-edge" baseline of the parent text content елемент.
text-before-edge: The alignment-point of the object being aligned is aligned with the "text-before-edge" baseline of the parent text content елемент.
middle: The alignment-point of the object being aligned is aligned with the "middle" baseline of the parent text content елемент.
central: The alignment-point of the object being aligned is aligned with the "central" baseline of the parent text content елемент.
after-edge: The alignment-point of the object being aligned is aligned with the "after-edge" baseline of the parent text content елемент.
text-after-edge: The alignment-point of the object being aligned is aligned with the "text-after-edge" baseline of the parent text content елемент.
ideographic: The alignment-point of the object being aligned is aligned with the "ideographic" baseline of the parent text content елемент.
alphabetic: The alignment-point of the object being aligned is aligned with the "alphabetic" baseline of the parent text content елемент.
hanging: The alignment-point of the object being aligned is aligned with the "hanging" baseline of the parent text content елемент.
mathematical: The alignment-point of the object being aligned is aligned with the "mathematical" baseline of the parent text content елемент.

‘baseline-shift’

Value:	baseline \| sub \| super \| <percentage> \| <length> \| inherit
Initial:	baseline
Applies to:	‘tspan’, ‘tref’, ‘altGlyph’, ‘textPath’ елементи
Inherited:	no
Percentages:	refers to the "line-height" of the ‘text’ елемент, which in the case of SVG is defined to be equal to the ‘font-size’
Media:	visual
Animatable:	yes

The ‘baseline-shift’ властивість allows repositioning of the dominant-baseline relative to the dominant-baseline of the parent text content елемент. The shifted object might be a sub- or superscript. Within the shifted object, the whole baseline-table is offset; not just a single baseline. The amount of the shift is determined from information from the parent text content елемент, the sub- or superscript offset from the nominal font of the parent text content елемент, percent of the "line-height" of the parent text content елемент or an absolute value.

In SVG, the ‘baseline-shift’ властивість represents a supplemental adjustment to the baseline tables. The ‘baseline-shift’ властивість shifts the baseline tables for each glyph to temporary new positions, for example to lift the glyph into superscript or subscript position, but it does not effect the current text position. When the current text position is adjusted after rendering a glyph to take into account glyph advance values, the adjustment happens as if there were no baseline shift.

‘baseline-shift’ властивості can nest. Each nested ‘baseline-shift’ is added to previous baseline shift values.

Values for the властивість have the following meaning:

baseline: There is no baseline shift; the dominant-baseline remains in its original position.
sub: The dominant-baseline is shifted to the default position for subscripts. The offset to this position is determined using the font data for the nominal font. Because in most fonts the subscript position is normally given relative to the "alphabetic" baseline, the user agent may compute the effective position for subscripts for superscripts when some other baseline is dominant. The suggested computation is to subtract the difference between the position of the dominant baseline and the position of the "alphabetic" baseline from the position of the subscript. The resulting offset is determined by multiplying the effective subscript position by the dominant baseline-table font-size. If there is no applicable font data the user agent may use heuristics to determine the offset.
super: The dominant-baseline is shifted to the default position for superscripts. The offset to this position is determined using the font data for the nominal font. Because in most fonts the superscript position is normally given relative to the "alphabetic" baseline, the user agent may compute the effective position for superscripts when some other baseline is dominant. The suggested computation is to subtract the difference between the position of the dominant baseline and the position of the "alphabetic" baseline from the position of the superscript. The resulting offset is determined by multiplying the effective superscript position by the dominant baseline-table font-size. If there is no applicable font data the user agent may use heuristics to determine the offset.
<percentage>: The computed value of the властивість is this percentage multiplied by the computed "line-height" of the ‘text’ елемент. The dominant-baseline is shifted in the shift direction (positive value) or opposite to the shift direction (negative value) of the parent text content елемент by the computed value. A value of "0%" is equivalent to "baseline".
<length>: The dominant-baseline is shifted in the shift direction (positive value) or opposite to the shift direction (negative value) of the parent text content елемент by the <length> value. A value of "0cm" is equivalent to "baseline".

10.10 Font selection властивості

SVG uses the following font specification властивості. Except for any additional information provided in this specification, the normative definition of these властивості is in CSS2 ([CSS2], chapter section 15.2). Any SVG-specific notes about these властивості are contained in the descriptions below.

Note also the rules for expressing the syntax of CSS властивість values ([CSS2], section 1.3.2).

‘font-family’

Value:	[[ <family-name> \| <generic-family> ],]* [<family-name> \| <generic-family>] \| inherit
Initial:	depends on user agent
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість indicates which font family is to be used to render the text, specified as a prioritized list of font family names and/or generic family names. Unless the family name corresponds to a CSS IDENT, it must be quoted. Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 15.2.2).

‘font-style’

Value:	normal \| italic \| oblique \| inherit
Initial:	normal
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість specifies whether the text is to be rendered using a normal, italic or oblique face. Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 15.2.3).

‘font-variant’

Value:	normal \| small-caps \| inherit
Initial:	normal
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість indicates whether the text is to be rendered using the normal glyphs for lowercase characters or using small-caps glyphs for lowercase characters. Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 15.2.3).

‘font-weight’

Value:	normal \| bold \| bolder \| lighter \| 100 \| 200 \| 300 \| 400 \| 500 \| 600 \| 700 \| 800 \| 900 \| inherit
Initial:	normal
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість refers to the boldness or lightness of the glyphs used to render the text, relative to other fonts in the same font family. Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 15.2.3).

‘font-stretch’

Value:	normal \| wider \| narrower \| ultra-condensed \| extra-condensed \| condensed \| semi-condensed \| semi-expanded \| expanded \| extra-expanded \| ultra-expanded \| inherit
Initial:	normal
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість indicates the desired amount of condensing or expansion in the glyphs used to render the text. Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 15.2.3).

‘font-size’

Value:	<absolute-size> \| <relative-size> \| <length> \| <percentage> \| inherit
Initial:	medium
Applies to:	text content елементи
Inherited:	yes, the computed value is inherited
Percentages:	refer to parent елемент's font size
Media:	visual
Animatable:	yes

This властивість refers to the size of the font from baseline to baseline when multiple lines of text are set solid in a multiline layout environment. For SVG, if a <length> is provided without a unit identifier (e.g., an unqualified number such as 128), the SVG user agent processes the <length> as a height value in the current user coordinate system.

If a <length> is provided with one of the unit identifiers (e.g., 12pt or 10%), then the SVG user agent converts the <length> into a corresponding value in the current user coordinate system by applying the rules described in Units.

Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 15.2.4).

‘font-size-adjust’

Value:	<number> \| none \| inherit
Initial:	none
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes (non-additive)

This властивість allows authors to specify an aspect value for an елемент that will preserve the x-height of the first choice font in a substitute font. Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 15.2.4).

‘font’

Value:	[ [ <'font-style'> \|\| <'font-variant'> \|\| <'font-weight'> ]? <'font-size'> [ / <'line-height'> ]? <'font-family'> ] \| caption \| icon \| menu \| message-box \| small-caption \| status-bar \| inherit
Initial:	see individual властивості
Applies to:	text content елементи
Inherited:	yes
Percentages:	allowed on 'font-size' and 'line-height' (Note: for the purposes of processing the ‘font’ властивість in SVG, 'line-height' is assumed to be equal the value for властивість ‘font-size’)
Media:	visual
Animatable:	yes (non-additive)

Shorthand властивість for setting ‘font-style’, ‘font-variant’, ‘font-weight’, ‘font-size’, ‘line-height’ and ‘font-family’. The ‘line-height’ властивість has no effect on text layout in SVG. For the purposes of the ‘font’ властивість, ‘line-height’ is assumed to be equal to the value of the ‘font-size’ властивість. Conforming SVG Viewers are not required to support the various system font options (caption, icon, menu, message-box, small-caption and status-bar) and can use a system font or one of the generic fonts instead.

Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 15.2.5).

10.11 Spacing властивості

Three властивості affect the space between characters and words:

‘kerning’ indicates whether the user agent should adjust inter-glyph spacing based on kerning tables that are included in the relevant font (i.e., enable auto-kerning) or instead disable auto-kerning and instead set inter-character spacing to a specific length (typically, zero).
‘letter-spacing’ indicates an amount of space that is to be added between text characters supplemental to any spacing due to the ‘kerning’ властивість.
‘word-spacing’ indicates the spacing behavior between words.

‘kerning’

Value:	auto \| <length> \| inherit
Initial:	auto
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

The value of auto indicates that the user agent should adjust inter-glyph spacing based on kerning tables that are included in the font that will be used (i.e., enable auto-kerning).

If a <length> is provided, then auto-kerning is disabled. Instead, inter-character spacing is set to the given <length>. The most common scenario, other than auto, is to set ‘kerning’ to a value of 0 so that auto-kerning is disabled.

If a <length> is provided without a unit identifier (e.g., an unqualified number such as 128), the SVG user agent processes the <length> as a width value in the current user coordinate system.

If a <length> is provided with one of the unit identifiers (e.g., .25em or 1%), then the SVG user agent converts the <length> into a corresponding value in the current user coordinate system by applying the rules described in Units.

When a <length> is provided, its value is added to the inter-character spacing value specified by the ‘letter-spacing’ властивість.

‘letter-spacing’

Value:	normal \| <length> \| inherit
Initial:	normal
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість specifies spacing behavior between text characters supplemental to any spacing due to the ‘kerning’ властивість.

For SVG, if a <length> is provided without a unit identifier (e.g., an unqualified number such as 128), the SVG user agent processes the <length> as a width value in the current user coordinate system.

Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 16.4).

‘word-spacing’

Value:	normal \| <length> \| inherit
Initial:	normal
Applies to:	text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість specifies spacing behavior between words. For SVG, if a <length> is provided without a unit identifier (e.g., an unqualified number such as 128), the SVG user agent processes the <length> as a width value in the current user coordinate system.

Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 16.4).

10.12 Text decoration

‘text-decoration’

Value:	none \| [ underline \|\| overline \|\| line-through \|\| blink ] \| inherit
Initial:	none
Applies to:	text content елементи
Inherited:	no (see prose)
Percentages:	N/A
Media:	visual
Animatable:	yes

This властивість describes decorations that are added to the text of an елемент. Conforming SVG Viewers are not required to support the blink value.

Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 16.3.1).

The CSS2 specification defines the behavior of the ‘text-decoration’ властивість using the terminology "block-level елементи" and "inline елементи". For the purposes of the ‘text-decoration’ властивість and SVG, a ‘text’ елемент represents a block-level елемент and any of the potential children of a ‘text’ елемент (e.g., a ‘tspan’) represent inline елементи.

Also, the CSS2 definition of ‘text-decoration’ specifies that the "color of the decorations" remain the same on descendant елементи. Since SVG offers a painting модель consisting of the ability to apply various types of paint (see Painting: Filling, Stroking and Marker Symbols) to both the interior (i.e., the "fill") and the outline (i.e., the "stroke") of text, for SVG the ‘text-decoration’ властивість is defined such that, for an елемент which has a specified value for the ‘text-decoration’ властивість, all decorations on its content and that of its descendants are rendered using the same fill and stroke властивості as are present on the given елемент. If the ‘text-decoration’ властивість is specified on a descendant, then that overrides the ancestor.

Because SVG allows text to be both filled and stroked, drawing order matters in some circumstances with text decorations. Text decoration drawing order should be as follows:

All text decorations except line-through should be drawn before the text is filled and stroked; thus, the text is rendered on top of these decorations.
Line-through should be drawn after the text is filled and stroked; thus, the line-through is rendered on top of the text.

Example textdecoration01 provides examples for ‘text-decoration’. The first line of text has no value for ‘text-decoration’, so the initial value of text-decoration:none is used. The second line shows text-decoration:line-through. The third line shows text-decoration:underline. The fourth line illustrates the rule whereby decorations are rendered using the same fill and stroke властивості as are present on the елемент for which the ‘text-decoration’ is specified. Since ‘text-decoration’ is specified on the ‘text’ елемент, all text within the ‘text’ елемент has its underline rendered with the same fill and stroke властивості as exist on the ‘text’ елемент (i.e., blue fill, red stroke), even though the various words have different fill and stroke властивість values. Якever, the word "different" explicitly specifies a value for ‘text-decoration’; thus, its underline is rendered using the fill and stroke властивості as the ‘tspan’ елемент that surrounds the word "different" (i.e., yellow fill, darkgreen stroke):

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="4cm" viewBox="0 0 1200 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example textdecoration01 - behavior of 'text-decoration' властивість</desc>
  <rect x="1" y="1" width="1198" height="398" fill="none" stroke="blue" stroke-width="2" />
  <g font-size="60" fill="blue" stroke="red" stroke-width="1" >
    <text x="100" y="75">Normal text</text>
    <text x="100" y="165" text-decoration="line-through" >Text with line-through</text>
    <text x="100" y="255" text-decoration="underline" >Underlined text</text>
    <text x="100" y="345" text-decoration="underline" >
      <tspan>One </tspan>
      <tspan fill="yellow" stroke="purple" >word </tspan>
      <tspan fill="yellow" stroke="black" >has </tspan>
      <tspan fill="yellow" stroke="darkgreen" text-decoration="underline" >different </tspan>
      <tspan fill="yellow" stroke="blue" >underlining</tspan>
    </text>
  </g>
</svg>

Example textdecoration01

View this example as SVG (SVG-enabled browsers only)

10.13 Text on a path

10.13.1 Вступ to text on a path

In addition to text drawn in a straight line, SVG also includes the ability to place text along the shape of a ‘path’ елемент. To specify that a block of text is to be rendered along the shape of a ‘path’, include the given text within a ‘textPath’ елемент which includes an ‘xlink:href’ атрибут with an IRI reference to a ‘path’ елемент.

10.13.2 The ‘textPath’ елемент

‘textPath’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’
‘a’
‘altGlyph’
‘animate’
‘animateColor’
‘set’
‘tref’
‘tspan’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘xlink:href’
‘startOffset’
‘method’
‘spacing’

DOM Інтерфейсs:

SVGTextPathElement

Attribute definitions:

startOffset = "<length>": An offset from the start of the ‘path’ for the initial current text position, calculated using the user agent's distance along the path algorithm.
If a <length> other than a percentage is given, then the ‘startOffset’ represents a distance along the path measured in the current user coordinate system.
If a percentage is given, then the ‘startOffset’ represents a percentage distance along the entire path. Thus, startOffset="0%" indicates the start point of the ‘path’ and startOffset="100%" indicates the end point of the ‘path’.

If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.
method = "align | stretch": Indicates the method by which text should be rendered along the path.
A value of align indicates that the glyphs should be rendered using simple 2x3 transformations such that there is no stretching/warping of the glyphs. Typically, supplemental rotation, scaling and translation transformations are done for each glyph to be rendered. As a result, with align, fonts where the glyphs are designed to be connected (e.g., cursive fonts), the connections may not align properly when text is rendered along a path.
A value of stretch indicates that the glyph outlines will be converted into paths, and then all end points and control points will be adjusted to be along the perpendicular vectors from the path, thereby stretching and possibly warping the glyphs. With this approach, connected glyphs, such as in cursive scripts, will maintain their connections.
If the атрибут is not specified, the effect is as if a value of align were specified.
Animatable: yes.
spacing = "auto | exact": Indicates how the user agent should determine the spacing between glyphs that are to be rendered along a path.
A value of exact indicates that the glyphs should be rendered exactly according to the spacing rules as specified in Text on a path layout rules.
A value of auto indicates that the user agent should use text-on-a-path layout algorithms to adjust the spacing between glyphs in order to achieve visually appealing results.
If the атрибут is not specified, the effect is as if a value of exact were specified.
Animatable: yes.
xlink:href = "<iri>": An IRI reference to the ‘path’ елемент onto which the glyphs will be rendered. If <iri> is an invalid reference (e.g., no such елемент exists, or the referenced елемент is not a ‘path’), then the ‘textPath’ елемент is in error and its entire contents shall not be rendered by the user agent.
Animatable: yes.

The path data coordinates within the referenced ‘path’ елемент are assumed to be in the same coordinate system as the current ‘text’ елемент, not in the coordinate system where the ‘path’ елемент is defined. The ‘transform’ атрибут on the referenced ‘path’ елемент represents a supplemental transformation relative to the current user coordinate system for the current ‘text’ елемент, including any adjustments to the current user coordinate system due to a possible ‘transform’ атрибут on the current ‘text’ елемент. For example, the following fragment of SVG content:

<svg xmlns="http://www.w3.org/2000/svg" 
     xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1">
  <g transform="translate(25,25)">
    <defs>
      <path id="path1" transform="scale(2)" d="..." fill="none" stroke="red"/>
    </defs>
  </g>
  <text transform="rotate(45)">
    <textPath xlink:href="#path1">Text along path1</textPath>
  </text>
</svg>

should have the same effect as the following:

<svg xmlns="http://www.w3.org/2000/svg" 
     xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1">
  <g transform="rotate(45)">
    <defs>
      <path id="path1" transform="scale(2)" d="..." fill="none" stroke="red"/>
    </defs>
    <text>
      <textPath xlink:href="#path1">Text along path1</textPath>
    </text>
  </g>
</svg>

Note that the transform="translate(25,25)" has no effect on the ‘textPath’ елемент, whereas the transform="rotate(45)" applies to both the ‘text’ and the use of the ‘path’ елемент as the referenced shape for text on a path.

Example toap01 provides a simple example of text on a path:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="3.6cm" viewBox="0 0 1000 300" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <defs>
    <path id="MyPath"
          d="M 100 200 
             C 200 100 300   0 400 100
             C 500 200 600 300 700 200
             C 800 100 900 100 900 100" />
  </defs>
  <desc>Example toap01 - simple text on a path</desc>

  <use xlink:href="#MyPath" fill="none" stroke="red"  />
  <text font-family="Verdana" font-size="42.5" fill="blue" >
    <textPath xlink:href="#MyPath">
      We go up, then we go down, then up again
    </textPath>
  </text>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example toap01

Example toap02 shows how ‘tspan’ елементи can be included within ‘textPath’ елементи to adjust styling атрибути and adjust the current text position before rendering a particular glyph. The first occurrence of the word "up" is filled with the color red. Attribute ‘dy’ is used to lift the word "up" from the baseline.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="3.6cm" viewBox="0 0 1000 300" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <defs>
    <path id="MyPath"
          d="M 100 200 
             C 200 100 300   0 400 100
             C 500 200 600 300 700 200
             C 800 100 900 100 900 100" />
  </defs>
  <desc>Example toap02 - tspan within textPath</desc>

  <use xlink:href="#MyPath" fill="none" stroke="red"  />
  <text font-family="Verdana" font-size="42.5" fill="blue" >
    <textPath xlink:href="#MyPath">
      We go 
      <tspan dy="-30" fill="red" >
        up
      </tspan>
      <tspan dy="30">
        ,
      </tspan>
      then we go down, then up again
    </textPath>
  </text>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example toap02

View this example as SVG (SVG-enabled browsers only)

Example toap03 demonstrates the use of the ‘startOffset’ атрибут on the ‘textPath’ елемент to specify the start position of the text string as a particular position along the path. Notice that glyphs that fall off the end of the path are not rendered (see text on a path layout rules).

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="3.6cm" viewBox="0 0 1000 300" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <defs>
    <path id="MyPath"
          d="M 100 200 
             C 200 100 300   0 400 100
             C 500 200 600 300 700 200
             C 800 100 900 100 900 100" />
  </defs>
  <desc>Example toap03 - text on a path with startOffset атрибут</desc>

  <use xlink:href="#MyPath" fill="none" stroke="red"  />
  <text font-family="Verdana" font-size="42.5" fill="blue" >
    <textPath xlink:href="#MyPath" startOffset="80%">
      We go up, then we go down, then up again
    </textPath>
  </text>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example toap03

View this example as SVG (SVG-enabled browsers only)

10.13.3 Text on a path layout rules

Conceptually, for text on a path the target path is stretched out into either a horizontal or vertical straight line segment. For horizontal text layout flows, the path is stretched out into a hypothetical horizontal line segment such that the start of the path is mapped to the left of the line segment. For vertical text layout flows, the path is stretched out into a hypothetical vertical line segment such that the start of the path is mapped to the top of the line segment. The standard text layout rules are applied to the hypothetical straight line segment and the result is mapped back onto the target path. Vertical and bidirectional text layout rules also apply to text on a path.

The reference orientation is determined individually for each glyph that is rendered along the path. For horizontal text layout flows, the reference orientation for a given glyph is the vector that starts at the intersection point on the path to which the glyph is attached and which points in the direction 90 degrees counter-clockwise from the angle of the curve at the intersection point. For vertical text layout flows, the reference orientation for a given glyph is the vector that starts at the intersection point on the path to which the glyph is attached and which points in the direction 180 degrees from the angle of the curve at the intersection point.

Example toap04 will be used to illustrate the particular layout rules for text on a path that supplement the basic text layout rules for straight line horizontal or vertical text.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="3.6cm" viewBox="0 0 1000 300" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <defs>
    <path id="MyPath"
          d="M 100 125 
             C 150 125 250 175 300 175
             C 350 175 450 125 500 125
             C 550 125 650 175 700 175
             C 750 175 850 125 900 125" />
  </defs>
  <desc>Example toap04 - text on a path layout rules</desc>

  <use xlink:href="#MyPath" fill="none" stroke="red"  />
  <text font-family="Verdana" font-size="60" fill="blue" letter-spacing="2" >
    <textPath xlink:href="#MyPath">
      Choose shame or get war 
    </textPath>
  </text>

  <!-- Show outline of canvas using 'rect' елемент -->
  <rect x="1" y="1" width="998" height="298"
        fill="none" stroke="blue" stroke-width="2" />
</svg>

Example toap04

View this example as SVG (SVG-enabled browsers only)

The following picture does an initial zoom in on the first glyph in the ‘text’ елемент.

The small dot above shows the point at which the glyph is attached to the path. The box around the glyph shows the glyph is rotated such that its horizontal axis is parallel to the tangent of the curve at the point at which the glyph is attached to the path. The box also shows the glyph's charwidth (i.e., the amount which the current text position advances horizontally when the glyph is drawn using horizontal text layout).

The next picture zooms in further to demonstrate the detailed layout rules.

For left-to-right horizontal text layout along a path (i.e., when the glyph orientation is perpendicular to the inline-progression-direction), the layout rules are as follows:

Determine the startpoint-on-the-path for the first glyph using атрибут ‘startOffset’ and властивість ‘text-anchor’. For text-anchor:start, startpoint-on-the-path is the point on the path which represents the point on the path which is ‘startOffset’ distance along the path from the start of the path, calculated using the user agent's distance along the path algorithm. For text-anchor:middle, startpoint-on-the-path is the point on the path which represents the point on the path which is [ ‘startOffset’ minus half of the total advance values for all of the glyphs in the ‘textPath’ елемент ] distance along the path from the start of the path, calculated using the user agent's distance along the path algorithm. For text-anchor:end, startpoint-on-the-path is the point on the path which represents the point on the path which is [ ‘startOffset’ minus the total advance values for all of the glyphs in the ‘textPath’ елемент ]. Before rendering the first glyph, the horizontal component of the startpoint-on-the-path is adjusted to take into account various horizontal alignment text властивості and атрибути, such as a ‘dx’ атрибут value on a ‘tspan’ елемент. (In the picture above, the startpoint-on-the-path is the leftmost dot on the path.)
Determine the glyph's charwidth (i.e., the amount which the current text position advances horizontally when the glyph is drawn using horizontal text layout). (In the picture above, the charwidth is the distance between the two dots at the side of the box.)
Determine the point on the curve which is charwidth distance along the path from the startpoint-on-the-path for this glyph, calculated using the user agent's distance along the path algorithm. This point is the endpoint-on-the-path for the glyph. (In the picture above, the endpoint-on-the-path for the glyph is the rightmost dot on the path.)
Determine the midpoint-on-the-path, which is the point on the path which is "halfway" (user agents can choose either a distance calculation or a parametric calculation) between the startpoint-on-the-path and the endpoint-on-the-path. (In the picture above, the midpoint-on-the-path is shown as a white dot.)
Determine the glyph-midline, which is the vertical line in the glyph's coordinate system that goes through the glyph's x-axis midpoint. (In the picture above, the glyph-midline is shown as a dashed line.)
Position the glyph such that the glyph-midline passes through the midpoint-on-the-path and is perpendicular to the line through the startpoint-on-the-path and the endpoint-on-the-path.
Align the glyph vertically relative to the midpoint-on-the-path based on властивість ‘alignment-baseline’ and any specified values for атрибут ‘dy’ on a ‘tspan’ елемент. In the example above, the ‘alignment-baseline’ властивість is unspecified, so the initial value of alignment-baseline:baseline will be used. There are no ‘tspan’ елементи; thus, the baseline of the glyph is aligned to the midpoint-on-the-path.
For each subsequent glyph, set a new startpoint-on-the-path as the previous endpoint-on-the-path, but with appropriate adjustments taking into account horizontal kerning tables in the font and current values of various атрибути and властивості, including spacing властивості and ‘tspan’ елементи with values provided for атрибути ‘dx’ and ‘dy’. All adjustments are calculated as distance adjustments along the path, calculated using the user agent's distance along the path algorithm.
Glyphs whose midpoint-on-the-path are off either end of the path are not rendered.
Continue rendering glyphs until there are no more glyphs.

Comparable rules are used for top-to-bottom vertical text layout along a path (i.e., when the glyph orientation is parallel with the inline-progression-direction), the layout rules are as follows:

Determine the startpoint-on-the-path using the same method as for horizontal text layout along a path, except that before rendering the first glyph, the horizontal component of the startpoint-on-the-path is adjusted to take into account various vertical alignment text властивості and атрибути, such as a ‘dy’ атрибут value on a ‘tspan’ елемент.
Determine the glyph's charheight (i.e., the amount which the current text position advances vertically when the glyph is drawn using vertical text layout).
Determine the point on the curve which is charheight distance along the path from the startpoint-on-the-path for this glyph, calculated using the user agent's distance along the path algorithm. This point is the endpoint-on-the-path for the glyph.
Determine the midpoint-on-the-path, which is the point on the path which is "halfway" (user agents can choose either a distance calculation or a parametric calculation) between the startpoint-on-the-path and the endpoint-on-the-path.
Determine the glyph-midline, which is the horizontal line in the glyph's coordinate system that goes through the glyph's y-axis midpoint.
Position the glyph such that the glyph-midline passes through the midpoint-on-the-path and is perpendicular to the line through the startpoint-on-the-path and the endpoint-on-the-path.
Align the glyph horizontally (where horizontal is relative to the glyph's coordinate system) relative to the midpoint-on-the-path based on властивість ‘alignment-baseline’ and any specified values for атрибут ‘dx’ on a ‘tspan’ елемент.
For each subsequent glyph, set a new startpoint-on-the-path as the previous endpoint-on-the-path, but with appropriate adjustments taking into account vertical kerning tables in the font and current values of various атрибути and властивості, including spacing властивості and ‘tspan’ елементи with values provided for атрибути ‘dx’ and ‘dy’. All adjustments are calculated as distance adjustments along the path, calculated using the user agent's distance along the path algorithm.
Glyphs whose midpoint-on-the-path are off either end of the path are not rendered.
Continue rendering glyphs until there are no more glyphs.

In the calculations above, if either the startpoint-on-the-path or the endpoint-on-the-path is off the end of the path, then extend the path beyond its end points with a straight line that is parallel to the tangent at the path at its end point so that the midpoint-on-the-path can still be calculated.

When the inline-progression-direction is horizontal, then any ‘x’ атрибути on ‘text’, ‘tspan’, ‘tref’ or ‘altGlyph’ елементи represent new absolute offsets along the path, thus providing explicit new values for startpoint-on-the-path. Any ‘y’ атрибути on ‘text’, ‘tspan’, ‘tref’ or ‘altGlyph’ елементи are ignored. When the inline-progression-direction is vertical, then any ‘y’ атрибути on ‘text’, ‘tspan’, ‘tref’ or ‘altGlyph’ елементи represent new absolute offsets along the path, thus providing explicit new values for startpoint-on-the-path. Any ‘x’ атрибути on ‘text’, ‘tspan’, ‘tref’ or ‘altGlyph’ елементи are ignored.

10.14 Alternate glyphs

There are situations such as ligatures, special-purpose fonts (e.g., a font for music symbols) or alternate glyphs for Asian text strings where it is required that a different set of glyphs is used than the glyph(s) which normally corresponds to the given character data.

10.14.1 The ‘altGlyph’ елемент

The ‘altGlyph’ елемент provides control over the glyphs used to render particular character data.

‘altGlyph’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any елементи or character data.

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘x’
‘y’
‘dx’
‘dy’
‘glyphRef’
‘format’
‘rotate’
‘xlink:href’

DOM Інтерфейсs:

SVGAltGlyphElement

Attribute definitions:

xlink:href = "<iri>": An IRI reference either to a ‘glyph’ елемент in an SVG document fragment or to an ‘altGlyphDef’ елемент.

If the reference is to a ‘glyph’ елемент and that glyph is available, then that glyph is rendered instead of the character(s) that are inside of the ‘altGlyph’ елемент.

If the reference is to an ‘altGlyphDef’ елемент, then if an appropriate set of alternate glyphs is located from processing the ‘altGlyphDef’ елемент, then those alternate glyphs are rendered instead of the character(s) that are inside of the ‘altGlyph’ елемент.

Animatable: no.
glyphRef = "<string>": The glyph identifier, the format of which is dependent on the ‘format’ of the given font. (Same meaning as the ‘glyphRef’ атрибут on the ‘glyphRef’ елемент.)
Animatable: no.
format = "<string>": The format of the given font. If the font is in one of the formats listed in CSS2 ([CSS2], section 15.3.5), such as TrueDoc™ Portable Font Resource or Embedded OpenType, then the <string> must contain the corresponding font format string, such as truedoc-pfr or embedded-opentype. (This атрибут has the same meaning as the ‘format’ атрибут on the ‘glyphRef’ елемент.)
Animatable: no.
x = "<list-of-coordinates>": The <coordinate> values are processed in the same manner as the ‘x’ атрибут on the ‘tspan’ елемент, with the following exception: If the referenced alternate glyphs are rendered instead of the Unicode characters inside the ‘altGlyph’ елемент, then any absolute X coordinates specified via an ‘x’ атрибут on this елемент or any ancestor ‘text’ or ‘tspan’ елементи for Unicode characters 2 through n within the ‘altGlyph’ елемент are ignored. Any absolute X coordinate specified via an ‘x’ атрибут on this елемент or any ancestor ‘text’ or ‘tspan’ елементи for the first Unicode character within the ‘altGlyph’ елемент sets a new absolute X coordinate for the current text position before rendering the first alternate glyph.
Animatable: yes.
y = "<list-of-coordinates>": The corresponding absolute Y coordinates for rendering the ‘altGlyph’ елемент.
Animatable: yes.
dx = "<list-of-lengths>": The <length> values are processed in the same manner as the ‘dx’ атрибут on the ‘tspan’ елемент, with the following exception: If the referenced alternate glyphs are rendered instead of the Unicode characters inside the ‘altGlyph’ елемент, then any relative X coordinates specified via an ‘dx’ атрибут on this елемент or any ancestor ‘text’ or ‘tspan’ елементи for Unicode characters 2 through n within the ‘altGlyph’ елемент are ignored. Any relative X coordinate specified via an ‘dx’ атрибут on this елемент or any ancestor ‘text’ or ‘tspan’ елементи for the first Unicode character within the ‘altGlyph’ елемент sets a new relative X coordinate for the current text position before rendering the first alternate glyph.
Animatable: yes.
dy = "<list-of-lengths>": The corresponding relative Y coordinates for rendering the ‘altGlyph’ елемент.
Animatable: yes.
rotate = "<list-of-numbers>": The <number> values are processed in the same manner as the ‘rotate’ атрибут on the ‘tspan’ елемент, with the following exception: If the referenced alternate glyphs are rendered instead of the Unicode characters inside the ‘altGlyph’ елемент, then any supplemental rotation values specified via an ‘rotate’ атрибут on this елемент or any ancestor ‘text’ or ‘tspan’ елементи for Unicode characters 2 through n within the ‘altGlyph’ елемент are ignored. Supplemental rotation values specified via an ‘rotate’ атрибут on this елемент or any ancestor ‘text’ or ‘tspan’ елементи for the first Unicode character within the ‘altGlyph’ елемент sets a new supplemental rotation angle before rendering the alternate glyphs.
Animatable: yes (non-additive).

If the references to alternate glyphs do not result in successful identification of alternate glyphs to use, then the character(s) that are inside of the ‘altGlyph’ елемент are rendered as if the ‘altGlyph’ елемент were a ‘tspan’ елемент instead.

An ‘altGlyph’ елемент either references a ‘glyph’ елемент or an ‘altGlyphDef’ елемент via its ‘xlink:href’ атрибут or identifies a glyph by means of font selection властивості, a glyph identifier and a font format. If the ‘xlink:href’ атрибут is specified, it takes precedence, and the other glyph identification атрибути and властивості are ignored.

10.14.2 The ‘altGlyphDef’, ‘altGlyphItem’ and ‘glyphRef’ елементи

The ‘altGlyphDef’ елемент defines a set of possible glyph substitutions.

‘altGlyphDef’

Categories:

None

Content модель:

Either:

one or more ‘glyphRef’ елементи, or
one or more ‘altGlyphItem’ елементи.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’

DOM Інтерфейсs:

SVGAltGlyphDefElement

An ‘altGlyphDef’ can contain either of the following:

In the simplest case, an ‘altGlyphDef’ contains one or more ‘glyphRef’ елементи. Each ‘glyphRef’ елемент references a single glyph within a particular font. If all of the referenced glyphs are available, then these glyphs are rendered instead of the character(s) inside of the referencing ‘altGlyph’ елемент. If any of the referenced glyphs are unavailable, then the character(s) that are inside of the ‘altGlyph’ елемент are rendered as if there were not an ‘altGlyph’ елемент surrounding those characters.
In the more complex case, an ‘altGlyphDef’ contains one or more ‘altGlyphItem’ елементи. Each ‘altGlyphItem’ represents a candidate set of substitute glyphs. Each ‘altGlyphItem’ contains one or more ‘glyphRef’ елементи. Each ‘glyphRef’ елемент references a single glyph within a particular font. The first ‘altGlyphItem’ in which all referenced glyphs are available is chosen. The glyphs referenced from this ‘altGlyphItem’ are rendered instead of the character(s) that are inside of the referencing ‘altGlyph’ елемент. If none of the ‘altGlyphItem’ елементи result in a successful match (i.e., none of the ‘altGlyphItem’ елементи has all of its referenced glyphs available), then the character(s) that are inside of the ‘altGlyph’ елемент are rendered as if there were not an ‘altGlyph’ елемент surrounding those characters.

The ‘altGlyphItem’ елемент defines a candidate set of possible glyph substitutions. The first ‘altGlyphItem’ елемент whose referenced glyphs are all available is chosen. Its glyphs are rendered instead of the character(s) that are inside of the referencing ‘altGlyph’ елемент.

‘altGlyphItem’

Categories:

None

Content модель:

One or more ‘glyphRef’ елементи.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’

DOM Інтерфейсs:

SVGAltGlyphItemElement

The ‘glyphRef’ елемент defines a possible glyph to use.

‘glyphRef’

Categories:

None

Content модель:

Empty.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘x’
‘y’
‘dx’
‘dy’
‘glyphRef’
‘format’
‘xlink:href’

DOM Інтерфейсs:

SVGGlyphRefElement

Attribute definitions:

xlink:href = "<iri>": An IRI reference to a ‘glyph’ елемент in an SVG document fragment. The referenced ‘glyph’ is rendered as an alternate glyph.
Animatable: no.
glyphRef = "<string>": The glyph identifier, the format of which is dependent on the ‘format’ of the given font.
Animatable: no.
format = "<string>": The format of the given font. If the font is in one of the formats listed in CSS2 ([CSS2], section 15.3.5), such as TrueDoc™ Portable Font Resource or Embedded OpenType, then the <string> must contain the corresponding font format string, such as truedoc-pfr or embedded-opentype.
Animatable: no.
x = "<number>": This value represents the new absolute X coordinate within the font's coordinate system for this glyph.
The font coordinate system is based on the em square модель described in the Fonts chapter of CSS2 ([CSS2], chapter 15).
If the атрибут is not specified, for the first ‘glyphRef’ child елемент, the effect is as if the атрибут were set to "0", whereas for subsequent ‘glyphRef’ child елементи, the effect is as if the атрибут were set to the end X coordinate from the previous ‘glyphRef’ елемент.
Animatable: no.
y = "<number>": The corresponding new absolute Y coordinate within the font's coordinate system for this glyph.
Animatable: no.
dx = "<number>": This value represents the relative X coordinate within the font's coordinate system for this glyph. The glyph is thus shifted by <number> units along the positive X axis within the font's coordinate system supplemental to the absolute X coordinate established by the ‘x’ атрибут (either due to an explicit ‘x’ атрибут or due to default value processing for the ‘x’ атрибут).
The font coordinate system is based on the em square модель described in the Fonts chapter of CSS2 ([CSS2], chapter 15).
If the атрибут is not specified, the effect is as if the атрибут were set to "0".
Animatable: no.
dy = "<number>": The corresponding number of units within the font's coordinate system to shift the glyph along the positive Y axis relative to the absolute Y coordinate established by the ‘y’ атрибут.
Animatable: no.

A ‘glyphRef’ either references a ‘glyph’ елемент in an SVG document fragment via its ‘xlink:href’ атрибут or identifies a glyph by means of font selection властивості, a glyph identifier and a font format. If insufficient атрибути and властивості have been specified to identify a glyph, then the ‘glyphRef’ is processed in the same manner as when a glyph reference is fully specified, but the given glyph is not available. If the ‘xlink:href’ атрибут is specified, it takes precedence, and the other glyph identification атрибути and властивості are ignored.

10.15 White space handling

SVG supports the standard XML атрибут ‘xml:space’ to specify the handling of white space characters within a given ‘text’ елемент's character data. Note that any child елемент of a ‘text’ елемент may also have an ‘xml:space’ атрибут which will apply to that child елемент's text content. The SVG user agent has special processing rules associated with this атрибут as described below. These are behaviors that occur subsequent to XML parsing [XML10] and any construction of a DOM.

‘xml:space’ is an inheritable атрибут which can have one of two values:

'default': (The initial/default value for ‘xml:space’.) When xml:space="default", the SVG user agent will do the following using a copy of the original character data content. First, it will remove all newline characters. Then it will convert all tab characters into space characters. Then, it will strip off all leading and trailing space characters. Then, all contiguous space characters will be consolidated.
'preserve': When xml:space="preserve", the SVG user agent will do the following using a copy of the original character data content. It will convert all newline and tab characters into space characters. Then, it will draw all space characters, including leading, trailing and multiple contiguous space characters. Thus, when drawn with xml:space="preserve", the string "a b" (three spaces between "a" and "b") will produce a larger separation between "a" and "b" than "a b" (one space between "a" and "b").

The following example illustrates that line indentation can be important when using xml:space="default". The fragment below show two pairs of similar ‘text’ елементи, with both ‘text’ елементи using xml:space="default". For these examples, there is no extra white space at the end of any of the lines (i.e., the line break occurs immediately after the last visible character).

[01]  <text xml:space='default'>
[02]    WS example
[03]    indented lines
[04]  </text>
[05]  <text xml:space='preserve'>WS example indented lines</text>
[06]
[07]  <text xml:space='default'>
[08]WS example
[09]non-indented lines
[10]  </text>
[11]  <text xml:space='preserve'>WS examplenon-indented lines</text>

The first pair of ‘text’ елементи above show the effect of indented character data. The атрибут xml:space="default" in the first ‘text’ елемент instructs the user agent to:

convert all tabs (if any) to space characters,
strip out all line breaks (i.e., strip out the line breaks at the end of lines [01], [02] and [03]),
strip out all leading space characters (i.e., strip out space characters before "WS example" on line [02]),
strip out all trailing space characters (i.e., strip out space characters before "</text>" on line [04]),
consolidate all intermediate space characters (i.e., the space characters before "indented lines" on line [03]) into a single space character.

The second pair of ‘text’ елементи above show the effect of non-indented character data. The атрибут xml:space="default" in the third ‘text’ елемент instructs the user agent to:

convert all tabs (if any) to space characters,
strip out all line breaks (i.e., strip out the line breaks at the end of lines [07], [08] and [09]),
strip out all leading space characters (there are no leading space characters in this example),
strip out all trailing space characters (i.e., strip out space characters before "</text>" on line [10]),
consolidate all intermediate space characters into a single space character (in this example, there are no intermediate space characters).

Note that XML parsers are required to convert the standard representations for a newline indicator (e.g., the literal two-character sequence "#xD#xA" or the stand-alone literals #xD or #xA) into the single character #xA before passing character data to the application. Thus, each newline in SVG will be represented by the single character #xA, no matter what representation for newlines might have been used in the original resource. (See XML end-of-line handling.)

Any features in the SVG language or the SVG DOM that are based on character position number, such as the ‘x’, ‘y’, ‘dx’, ‘dy’ and ‘rotate’ атрибути on the ‘text’, ‘tspan’, ‘tref’ and ‘altGlyph’ елементи, are based on character position after applying the white space handling rules described here. In particular, if xml:space="default", it is often the case that white space characters are removed as part of processing. Character position numbers index into the text string after the white space characters have been removed per the rules in this section.

Note that a glyph corresponding to a whitespace character should only be displayed as a visible but blank space, even if the glyph itself happens to be non-blank. See display of unsupported characters [UNICODE].

The ‘xml:space’ атрибут is:

Animatable: no.

10.16 Text selection and clipboard operations

Conforming SVG viewers on systems which have the capacity for text selection (e.g., systems which are equipped with a pointer device such as a mouse) and which have system clipboards for copy/paste operations are required to support:

user selection of text strings in SVG content
the ability to copy selected text strings to the system clipboard

A text selection operation starts when all of the following occur:

the user positions the pointing device over a glyph that has been rendered as part of a ‘text’ елемент, initiates a select operation (e.g., pressing the standard system mouse button for select operations) and then moves the pointing device while continuing the select operation (e.g., continuing to press the standard system mouse button for select operations)
no other visible graphics елемент has been painted above the glyph at the point at which the pointing device was clicked
no links or events have been assigned to the ‘text’, ‘tspan’ or ‘textPath’ елемент(s) (or their ancestors) associated with the given glyph.

As the text selection operation proceeds (e.g., the user continues to press the given mouse button), all associated events with other graphics елементи are ignored (i.e., the text selection operation is modal) and the SVG user agent shall dynamically indicate which characters are selected by an appropriate highlighting technique, such as redrawing the selected glyphs with inverse colors. As the pointer is moved during the text selection process, the end glyph for the text selection operation is the glyph within the same ‘text’ елемент whose glyph cell is closest to the pointer. All characters within the ‘text’ елемент whose position within the ‘text’ елемент is between the start of selection and end of selection shall be highlighted, regardless of position on the canvas and regardless of any graphics елементи that might be above the end of selection point.

Once the text selection operation ends (e.g., the user releases the given mouse button), the selected text will stay highlighted until an event occurs which cancels text selection, such as a pointer device activation event (e.g., pressing a mouse button).

Detailed rules for determining which characters to highlight during a text selection operation are provided in Text selection implementation notes.

For systems which have system clipboards, the SVG user agent is required to provide a user interface for initiating a copy of the currently selected text to the system clipboard. It is sufficient for the SVG user agent to post the selected text string in the system's appropriate clipboard format for plain text, but it is preferable if the SVG user agent also posts a rich text alternative which captures the various font властивості associated with the given text string.

For bidirectional text, the user agent must support text selection in logical order, which will result in discontinuous highlighting of glyphs due to the bidirectional reordering of characters. User agents can provide an alternative ability to select bidirectional text in visual rendering order (i.e., after bidirectional text layout algorithms have been applied), with the result that selected character data might be discontinuous logically. In this case, if the user requests that bidirectional text be copied to the clipboard, then the user agent is required to make appropriate adjustments to copy only the visually selected characters to the clipboard.

When feasible, it is recommended that generators of SVG attempt to order their text strings to facilitate properly ordered text selection within SVG viewing applications such as Web browsers.

10.17 DOM interfaces

10.17.1 Інтерфейс SVGTextContentElement

The SVGTextContentElement is inherited by various text-related interfaces, such as SVGTextElement, SVGTSpanElement, SVGTRefElement, SVGAltGlyphElement and SVGTextPathElement.

For the methods on this interface that refer to an index to a character or a number of characters, these references are to be interpreted as an index to a UTF-16 code unit or a number of UTF-16 code units, respectively. This is for consistency with DOM Level 2 Core, where methods on the CharacterData interface use UTF-16 code units as indexes and counts within the character data. Thus for example, if the text content of a ‘text’ елемент is a single non-BMP character, such as U+10000, then invoking getNumberOfChars on that елемент will return 2 since there are two UTF-16 code units (the surrogate pair) used to represent that one character.

interface SVGTextContentElement : SVGElement,
                                  SVGTests,
                                  SVGLangSpace,
                                  SVGExternalResourcesRequired,
                                  SVGStylable {

  // lengthAdjust Types
  const unsigned short LENGTHADJUST_UNKNOWN = 0;
  const unsigned short LENGTHADJUST_SPACING = 1;
  const unsigned short LENGTHADJUST_SPACINGANDGLYPHS = 2;

  readonly атрибут SVGAnimatedLength textLength;
  readonly атрибут SVGAnimatedEnumeration lengthAdjust;

  long getNumberOfChars();
  float getComputedTextLength();
  float getSubStringLength(in unsigned long charnum, in unsigned long nchars) raises(DOMException);
  SVGPoint getStartPositionOfChar(in unsigned long charnum) raises(DOMException);
  SVGPoint getEndPositionOfChar(in unsigned long charnum) raises(DOMException);
  SVGRect getExtentOfChar(in unsigned long charnum) raises(DOMException);
  float getRotationOfChar(in unsigned long charnum) raises(DOMException);
  long getCharNumAtPosition(in SVGPoint point);
  void selectSubString(in unsigned long charnum, in unsigned long nchars) raises(DOMException);
};

Constants in group “lengthAdjust Types”:

LENGTHADJUST_UNKNOWN (unsigned short): The enumeration was set to a value that is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
LENGTHADJUST_SPACING (unsigned short): Corresponds to value 'spacing'.
LENGTHADJUST_SPACINGANDGLYPHS (unsigned short): Corresponds to value 'spacingAndGlyphs'.

Attributes:

textLength (readonly SVGAnimatedLength): Corresponds to атрибут ‘textLength’ on the given елемент.
lengthAdjust (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘lengthAdjust’ on the given елемент. The value must be one of the length adjust constants defined on this interface.

Operations:

long getNumberOfChars()

Returns the total number of characters available for rendering within the current елемент, which includes referenced characters from ‘tref’ reference, regardless of whether they will be rendered. Effectively, this is equivalent to the length of the Node::textContent атрибут from DOM Level 3 Core ([DOM3], section 1.4), if that атрибут also expanded ‘tref’ елементи.

Returns: Total number of characters.

float getComputedTextLength()

The total sum of all of the advance values from rendering all of the characters within this елемент, including the advance value on the glyphs (horizontal or vertical), the effect of властивості ‘kerning’, ‘letter-spacing’ and ‘word-spacing’ and adjustments due to атрибути ‘dx’ and ‘dy’ on ‘tspan’ елементи. For non-rendering environments, the user agent shall make reasonable assumptions about glyph metrics.

Returns: The text advance distance.

float getSubStringLength(in unsigned long charnum, in unsigned long nchars)

The total sum of all of the advance values from rendering the specified substring of the characters, including the advance value on the glyphs (horizontal or vertical), the effect of властивості ‘kerning’, ‘letter-spacing’ and ‘word-spacing’ and adjustments due to атрибути ‘dx’ and ‘dy’ on ‘tspan’ елементи. For non-rendering environments, the user agent shall make reasonable assumptions about glyph metrics. If multiple consecutive characters are rendered inseparably (e.g., as a single glyph or a sequence of glyphs, or because the range encompasses half of a surrogate pair), and nchars is greater than 0 then the measured range shall be expanded so that each of the inseparable characters are included.

Parameters

unsigned long charnum

The index of the first character in the substring, where the first character has an index of 0.
unsigned long nchars

The number of characters in the substring. If nchars specifies more characters than are available, then the substring will consist of all characters starting with charnum until the end of the list of characters.

Returns

The text advance distance.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if charnum or nchars is negative or if charnum is greater than or equal to the number of characters at this node.

SVGPoint getStartPositionOfChar(in unsigned long charnum)

Returns the current text position before rendering the character in the user coordinate system for rendering the glyph(s) that correspond to the specified character. The current text position has already taken into account the effects of any inter-character adjustments due to властивості ‘kerning’, ‘letter-spacing’ and ‘word-spacing’ and adjustments due to атрибути ‘x’, ‘y’, ‘dx’ and ‘dy’. If multiple consecutive characters are rendered inseparably (e.g., as a single glyph or a sequence of glyphs), then each of the inseparable characters will return the start position for the first glyph.

Parameters

unsigned long charnum

The index of the character, where the first character has an index of 0.

Returns

The character's start position.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the charnum is negative or if charnum is greater than or equal to the number of characters at this node.

SVGPoint getEndPositionOfChar(in unsigned long charnum)

Returns the current text position after rendering the character in the user coordinate system for rendering the glyph(s) that correspond to the specified character. This current text position does not take into account the effects of any inter-character adjustments to prepare for the next character, such as властивості ‘kerning’, ‘letter-spacing’ and ‘word-spacing’ and adjustments due to атрибути ‘x’, ‘y’, ‘dx’ and ‘dy’. If multiple consecutive characters are rendered inseparably (e.g., as a single glyph or a sequence of glyphs), then each of the inseparable characters will return the end position for the last glyph.

Parameters

unsigned long charnum

The index of the character, where the first character has an index of 0.

Returns

The character's end position.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the charnum is negative or if charnum is greater than or equal to the number of characters at this node.

SVGRect getExtentOfChar(in unsigned long charnum)

Returns a tightest rectangle which defines the minimum and maximum X and Y values in the user coordinate system for rendering the glyph(s) that correspond to the specified character. The calculations assume that all glyphs occupy the full standard glyph cell for the font. If multiple consecutive characters are rendered inseparably (e.g., as a single glyph or a sequence of glyphs), then each of the inseparable characters will return the same extent.

Parameters

unsigned long charnum

The index of the character, where the first character has an index of 0.

Returns

The rectangle which encloses all of the rendered glyph(s).

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the charnum is negative or if charnum is greater than or equal to the number of characters at this node.

float getRotationOfChar(in unsigned long charnum)

Returns the rotation value relative to the current user coordinate system used to render the glyph(s) corresponding to the specified character. If multiple glyph(s) are used to render the given character and the glyphs each have different rotations (e.g., due to text-on-a-path), the user agent shall return an average value (e.g., the rotation angle at the midpoint along the path for all glyphs used to render this character). The rotation value represents the rotation that is supplemental to any rotation due to властивості ‘glyph-orientation-horizontal’ and ‘glyph-orientation-vertical’; thus, any glyph rotations due to these властивості are not included into the returned rotation value. If multiple consecutive characters are rendered inseparably (e.g., as a single glyph or a sequence of glyphs), then each of the inseparable characters will return the same rotation value.

Parameters

unsigned long charnum

The index of the character, where the first character has an index of 0.

Returns

The rotation angle.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if the charnum is negative or if charnum is greater than or equal to the number of characters at this node.

long getCharNumAtPosition(in SVGPoint point)

Returns the index of the character whose corresponding glyph cell bounding box contains the specified point. The calculations assume that all glyphs occupy the full standard glyph cell for the font. If no such character exists, a value of -1 is returned. If multiple such characters exist, the character within the елемент whose glyphs were rendered last (i.e., take into account any reordering such as for bidirectional text) is used. If multiple consecutive characters are rendered inseparably (e.g., as a single glyph or a sequence of glyphs), then the user agent shall allocate an equal percentage of the text advance amount to each of the contributing characters in determining which of the characters is chosen.

Parameters

SVGPoint point

A point in user space.

Returns

The index of the character which is at the given point, where the first character has an index of 0.

void selectSubString(in unsigned long charnum, in unsigned long nchars)

Causes the specified substring to be selected just as if the user selected the substring interactively.

Parameters

unsigned long charnum

The index of the start character which is at the given point, where the first character has an index of 0.
unsigned long nchars

The number of characters in the substring. If nchars specifies more characters than are available, then the substring will consist of all characters starting with charnum until the end of the list of characters.

Exceptions

DOMException, code INDEX_SIZE_ERR: Raised if charnum or nchars is negative or if charnum is greater than or equal to the number of characters at this node.

10.17.2 Інтерфейс SVGTextPositioningElement

The SVGTextPositioningElement interface is inherited by text-related interfaces: SVGTextElement, SVGTSpanElement, SVGTRefElement and SVGAltGlyphElement.

interface SVGTextPositioningElement : SVGTextContentElement {
  readonly атрибут SVGAnimatedLengthList x;
  readonly атрибут SVGAnimatedLengthList y;
  readonly атрибут SVGAnimatedLengthList dx;
  readonly атрибут SVGAnimatedLengthList dy;
  readonly атрибут SVGAnimatedNumberList rotate;
};

Attributes:

x (readonly SVGAnimatedLengthList): Corresponds to атрибут ‘x’ on the given елемент.
y (readonly SVGAnimatedLengthList): Corresponds to атрибут ‘y’ on the given елемент.
dx (readonly SVGAnimatedLengthList): Corresponds to атрибут ‘dx’ on the given елемент.
dy (readonly SVGAnimatedLengthList): Corresponds to атрибут ‘dy’ on the given елемент.
rotate (readonly SVGAnimatedNumberList): Corresponds to атрибут ‘rotate’ on the given елемент.

10.17.3 Інтерфейс SVGTextElement

The SVGTextElement interface corresponds to the ‘text’ елемент.

interface SVGTextElement : SVGTextPositioningElement,
                           SVGTransformable {
};

10.17.4 Інтерфейс SVGTSpanElement

The SVGTSpanElement interface corresponds to the ‘tspan’ елемент.

interface SVGTSpanElement : SVGTextPositioningElement {
};

10.17.5 Інтерфейс SVGTRefElement

The SVGTRefElement interface corresponds to the ‘tref’ елемент.

interface SVGTRefElement : SVGTextPositioningElement,
                           SVGURIReference {
};

10.17.6 Інтерфейс SVGTextPathElement

The SVGTextPathElement interface corresponds to the ‘textPath’ елемент.

interface SVGTextPathElement : SVGTextContentElement,
                               SVGURIReference {

  // textPath Method Types
  const unsigned short TEXTPATH_METHODTYPE_UNKNOWN = 0;
  const unsigned short TEXTPATH_METHODTYPE_ALIGN = 1;
  const unsigned short TEXTPATH_METHODTYPE_STRETCH = 2;

  // textPath Spacing Types
  const unsigned short TEXTPATH_SPACINGTYPE_UNKNOWN = 0;
  const unsigned short TEXTPATH_SPACINGTYPE_AUTO = 1;
  const unsigned short TEXTPATH_SPACINGTYPE_EXACT = 2;

  readonly атрибут SVGAnimatedLength startOffset;
  readonly атрибут SVGAnimatedEnumeration method;
  readonly атрибут SVGAnimatedEnumeration spacing;
};

Constants in group “textPath Method Types”:

TEXTPATH_METHODTYPE_UNKNOWN (unsigned short): The enumeration was set to a value that is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
TEXTPATH_METHODTYPE_ALIGN (unsigned short): Corresponds to value 'align'.
TEXTPATH_METHODTYPE_STRETCH (unsigned short): Corresponds to value 'stretch'.

Constants in group “textPath Spacing Types”:

TEXTPATH_SPACINGTYPE_UNKNOWN (unsigned short): The enumeration was set to a value that is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
TEXTPATH_SPACINGTYPE_AUTO (unsigned short): Corresponds to value 'auto'.
TEXTPATH_SPACINGTYPE_EXACT (unsigned short): Corresponds to value 'exact'.

Attributes:

startOffset (readonly SVGAnimatedLength): Corresponds to атрибут ‘startOffset’ on the given ‘textPath’ елемент.
method (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘method’ on the given ‘textPath’ елемент.
spacing (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘spacing’ on the given ‘textPath’ елемент.

10.17.7 Інтерфейс SVGAltGlyphElement

The SVGAltGlyphElement interface corresponds to the ‘altGlyph’ елемент.

interface SVGAltGlyphElement : SVGTextPositioningElement,
                               SVGURIReference {
  атрибут DOMString glyphRef setraises(DOMException);
  атрибут DOMString format setraises(DOMException);
};

Attributes:

glyphRef (DOMString)

Corresponds to атрибут ‘glyphRef’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

format (DOMString)

Corresponds to атрибут ‘format’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

10.17.8 Інтерфейс SVGAltGlyphDefElement

The SVGAltGlyphDefElement interface corresponds to the ‘altGlyphDef’ елемент.

interface SVGAltGlyphDefElement : SVGElement {
};

10.17.9 Інтерфейс SVGAltGlyphItemElement

The SVGAltGlyphItemElement interface corresponds to the ‘altGlyphItem’ елемент.

interface SVGAltGlyphItemElement : SVGElement {
};

10.17.10 Інтерфейс SVGGlyphRefElement

The SVGGlyphRefElement interface corresponds to the ‘glyphRef’ елемент.

interface SVGGlyphRefElement : SVGElement,
                               SVGURIReference,
                               SVGStylable {
  атрибут DOMString glyphRef setraises(DOMException);
  атрибут DOMString format setraises(DOMException);
  атрибут float x setraises(DOMException);
  атрибут float y setraises(DOMException);
  атрибут float dx setraises(DOMException);
  атрибут float dy setraises(DOMException);
};

Attributes:

glyphRef (DOMString)

Corresponds to атрибут ‘glyphRef’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

format (DOMString)

Corresponds to атрибут ‘format’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

x (float)

Corresponds to атрибут ‘x’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

y (float)

Corresponds to атрибут ‘y’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

dx (float)

Corresponds to атрибут ‘dx’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

dy (float)

Corresponds to атрибут ‘dy’ on the given елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

11 Painting: Filling, Stroking and Marker Symbols

11.1 Вступ
11.2 Specifying paint
11.3 Fill Properties
11.4 Stroke Properties
11.5 Controlling visibility
11.6 Markers
11.7 Rendering властивості
11.8 Inheritance of painting властивості
11.9 DOM interfaces
- 11.9.1 Інтерфейс SVGPaint
- 11.9.2 Інтерфейс SVGMarkerElement

11.1 Вступ

‘path’ елементи, ‘text’ елементи and basic shapes can be filled (which means painting the interior of the object) and stroked (which means painting along the outline of the object). Filling and stroking both can be thought of in more general terms as painting operations.

Certain елементи (i.e., ‘path’, ‘polyline’, ‘polygon’ and ‘line’ елементи) can also have marker symbols drawn at their vertices.

With SVG, you can paint (i.e., fill or stroke) with:

a single color
a gradient (linear or radial)
a pattern (vector or image, possibly tiled)
custom paints available via extensibility

SVG uses the general notion of a paint server. Paint servers are specified using a IRI reference on a ‘fill’ or ‘stroke’ властивість. Gradients and patterns are just specific types of paint servers.

11.2 Specifying paint

Properties ‘fill’ and ‘stroke’ take on a value of type <paint>, which is specified as follows:

<paint>:

none: Indicates that no paint is applied.
currentColor: Indicates that painting is done using the current animated value of the color specified by the ‘color’ властивість. This mechanism is provided to facilitate sharing of color атрибути between parent grammars such as other (non-SVG) XML. This mechanism allows you to define a style in your HTML which sets the ‘color’ властивість and then pass that style to the SVG user agent so that your SVG text will draw in the same color.
<color> [<icccolor>]: <color> is the explicit color (in the sRGB color space [SRGB]) to be used to paint the current object. SVG supports all of the syntax alternatives for <color> defined in CSS2 ([CSS2], section 4.3.6), with the exception that SVG contains an expanded list of recognized color keywords names. If an optional ICC color specification [ICC42] is provided, then the user agent searches the color profile description database for a color profile description entry whose name descriptor matches the <name> part of the <icccolor> and uses the last matching entry that is found. (If no match is found, then the ICC color specification is ignored.) The comma and/or whitespace separated list of <number>s is a set of ICC-profile-specific color values. (In most cases, the <number>s will be in the range 0 to 1.) On platforms which support ICC-based color management, the <icccolor> gets precedence over the <color> (which is in the sRGB color space). Note that color interpolation occurs in an RGB color space even if an ICC-based color specification is provided (see ‘color-interpolation’ and ‘color-interpolation-filters’). For more on ICC-based colors, refer to Color profile descriptions.
<funciri> [ none | currentColor | <color> [<icccolor>] ]: The <funciri> is used to identify a paint server such as a gradient, a pattern or a custom paint defined by an extension (see Extensibility). The <funciri> points to the paint server (e.g., a gradient or pattern) to be used to paint the current object. If the IRI reference is not valid (e.g., it points to an object that doesn't exist or the object is not a valid paint server), then the paint method following the <funciri> (i.e., none | currentColor | <color> [<icccolor>] is used if provided; otherwise, the document is in error (see Error processing).

11.3 Fill Properties

‘fill’

Value:	<paint> (See Specifying paint)
Initial:	black
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

The ‘fill’ властивість paints the interior of the given graphical елемент. The area to be painted consists of any areas inside the outline of the shape. To determine the inside of the shape, all subpaths are considered, and the interior is determined according to the rules associated with the current value of the ‘fill-rule’ властивість. The zero-width geometric outline of a shape is included in the area to be painted.

The fill operation fills open subpaths by performing the fill operation as if an additional "closepath" command were added to the path to connect the last point of the subpath with the first point of the subpath. Thus, fill operations apply to both open subpaths within ‘path’ елементи (i.e., subpaths without a closepath command) and ‘polyline’ елементи.

‘fill-rule’

Value:	nonzero \| evenodd \| inherit
Initial:	nonzero
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

The ‘fill-rule’ властивість indicates the algorithm which is to be used to determine what parts of the canvas are included inside the shape. For a simple, non-intersecting path, it is intuitively clear what region lies "inside"; however, for a more complex path, such as a path that intersects itself or where one subpath encloses another, the interpretation of "inside" is not so obvious.

The ‘fill-rule’ властивість provides two options for how the inside of a shape is determined:

nonzero

This rule determines the "insideness" of a point on the canvas by drawing a ray from that point to infinity in any direction and then examining the places where a segment of the shape crosses the ray. Starting with a count of zero, add one each time a path segment crosses the ray from left to right and subtract one each time a path segment crosses the ray from right to left. After counting the crossings, if the result is zero then the point is outside the path. Otherwise, it is inside. The following drawing illustrates the nonzero rule:

Image showing nonzero fill rule

evenodd

This rule determines the "insideness" of a point on the canvas by drawing a ray from that point to infinity in any direction and counting the number of path segments from the given shape that the ray crosses. If this number is odd, the point is inside; if even, the point is outside. The following drawing illustrates the evenodd rule:

Image showing evenodd fill rule

View this example as SVG (SVG-enabled browsers only)

(Note: the above explanations do not specify what to do if a path segment coincides with or is tangent to the ray. Since any ray will do, one may simply choose a different ray that does not have such problem intersections.)

‘fill-opacity’

Value:	<opacity-value> \| inherit
Initial:	1
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

‘fill-opacity’ specifies the opacity of the painting operation used to paint the interior the current object. (See Painting shapes and text.)

<opacity-value>: The opacity of the painting operation used to fill the current object, as a <number>. Any values outside the range 0.0 (fully transparent) to 1.0 (fully opaque) will be clamped to this range. (See Clamping values which are restricted to a particular range.)

Related властивості: ‘stroke-opacity’ and ‘opacity’.

11.4 Stroke Properties

The following are the властивості which affect how an елемент is stroked.

In all cases, all stroking властивості which are affected by directionality, such as those having to do with dash patterns, must be rendered such that the stroke operation starts at the same point at which the graphics елемент starts. In particular, for ‘path’ елементи, the start of the path is the first point of the initial "moveto" command.

For stroking властивості such as dash patterns whose computations are dependent on progress along the outline of the graphics елемент, distance calculations are required to utilize the SVG user agent's standard Distance along a path algorithms.

When stroking is performed using a complex paint server, such as a gradient or a pattern, the stroke operation must be identical to the result that would have occurred if the geometric shape defined by the geometry of the current graphics елемент and its associated stroking властивості were converted to an equivalent ‘path’ елемент and then filled using the given paint server.

‘stroke’

Value:	<paint> (See Specifying paint)
Initial:	none
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

The ‘stroke’ властивість paints along the outline of the given graphical елемент.

A subpath (see Paths) consisting of a single moveto shall not be stroked. Any zero length subpath shall not be stroked if the ‘stroke-linecap’ властивість has a value of butt but shall be stroked if the ‘stroke-linecap’ властивість has a value of round or square, producing respectively a circle or a square centered at the given point. Examples of zero length subpaths include 'M 10,10 L 10,10', 'M 20,20 h 0', 'M 30,30 z' and 'M 40,40 c 0,0 0,0 0,0'.

‘stroke-width’

Value:	<percentage> \| <length> \| inherit
Initial:	1
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	Yes
Media:	visual
Animatable:	yes

This властивість specifies the width of the stroke on the current object. If a <percentage> is used, the value represents a percentage of the current viewport. (See Units.)

A zero value causes no stroke to be painted. A negative value is an error (see Error processing).

‘stroke-linecap’

Value:	butt \| round \| square \| inherit
Initial:	butt
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

‘stroke-linecap’ specifies the shape to be used at the end of open subpaths when they are stroked. For further details see the path implementation notes.

butt: See drawing below.
round: See drawing below.
square: See drawing below.

Image showing stroke-linecap alternatives

View this example as SVG (SVG- and CSS-enabled browsers only)

‘stroke-linejoin’

Value:	miter \| round \| bevel \| inherit
Initial:	miter
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

‘stroke-linejoin’ specifies the shape to be used at the corners of paths or basic shapes when they are stroked. For further details see the path implementation notes.

miter: See drawing below.
round: See drawing below.
bevel: See drawing below.

Image showing stroke-linejoin alternatives

View this example as SVG (SVG- and CSS-enabled browsers only)

‘stroke-miterlimit’

Value:	<miterlimit> \| inherit
Initial:	4
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

When two line segments meet at a sharp angle and miter joins have been specified for ‘stroke-linejoin’, it is possible for the miter to extend far beyond the thickness of the line stroking the path. The ‘stroke-miterlimit’ imposes a limit on the ratio of the miter length to the ‘stroke-width’. When the limit is exceeded, the join is converted from a miter to a bevel.

<miterlimit>: The limit on the ratio of the miter length to the ‘stroke-width’. The value of <miterlimit> must be a <number> greater than or equal to 1. Any other value is an error (see Error processing).

The ratio of miter length (distance between the outer tip and the inner corner of the miter) to ‘stroke-width’ is directly related to the angle (theta) between the segments in user space by the formula:

miterLength / stroke-width = 1 / sin ( theta / 2 )

For example, a miter limit of 1.414 converts miters to bevels for theta less than 90 degrees, a limit of 4.0 converts them for theta less than approximately 29 degrees, and a limit of 10.0 converts them for theta less than approximately 11.5 degrees.

‘stroke-dasharray’

Value:	none \| <dasharray> \| inherit
Initial:	none
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	yes (see below)
Media:	visual
Animatable:	yes (non-additive)

‘stroke-dasharray’ controls the pattern of dashes and gaps used to stroke paths. <dasharray> contains a list of comma and/or white space separated <length>s and <percentage>s that specify the lengths of alternating dashes and gaps. If an odd number of values is provided, then the list of values is repeated to yield an even number of values. Thus, stroke-dasharray: 5,3,2 is equivalent to stroke-dasharray: 5,3,2,5,3,2.

none

Indicates that no dashing is used. If stroked, the line is drawn solid.

<dasharray>

A list of comma and/or white space separated <length>s (which can have a unit identifier) and <percentage>s. A percentage represents a distance as a percentage of the current viewport (see Units). A negative value is an error (see Error processing). If the sum of the values is zero, then the stroke is rendered as if a value of none were specified. For further details see the path implementation notes.

The grammar for <dasharray> is as follows:

dasharray ::= (length | percentage) (comma-wsp dasharray)?

‘stroke-dashoffset’

Value:	<percentage> \| <length> \| inherit
Initial:	0
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	see prose
Media:	visual
Animatable:	yes

‘stroke-dashoffset’ specifies the distance into the dash pattern to start the dash.

If a <percentage> is used, the value represents a percentage of the current viewport (see Units).

Values can be negative.

‘stroke-opacity’

Value:	<opacity-value> \| inherit
Initial:	1
Applies to:	shapes and text content елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

‘stroke-opacity’ specifies the opacity of the painting operation used to stroke the current object. (See Painting shapes and text.)

<opacity-value>: The opacity of the painting operation used to stroke the current object, as a <number>. Any values outside the range 0.0 (fully transparent) to 1.0 (fully opaque) will be clamped to this range. (See Clamping values which are restricted to a particular range.)

Related властивості: ‘fill-opacity’ and ‘opacity’.

11.5 Controlling visibility

SVG uses two властивості, ‘display’ and ‘visibility’, to control the visibility of graphical елементи or (in the case of the ‘display’ властивість) container елементи.

The differences between the two властивості are as follows:

When applied to a container елемент, setting ‘display’ to none causes the container and all of its children to be invisible; thus, it acts on групи of елементи as a group. ‘visibility’, however, only applies to individual graphics елементи. Setting ‘visibility’ to hidden on a ‘g’ will make its children invisible as long as the children do not specify their own ‘visibility’ властивості as visible. Note that ‘visibility’ is not an inheritable властивість.
When the ‘display’ властивість is set to none, then the given елемент does not become part of the rendering tree. With ‘visibility’ set to hidden, however, processing occurs as if the елемент were part of the rendering tree and still taking up space, but not actually rendered onto the canvas. This distinction has implications for the ‘tspan’, ‘tref’ and ‘altGlyph’ елементи, event processing, for bounding box calculations and for calculation of clipping paths. If ‘display’ is set to none on a ‘tspan’, ‘tref’ or ‘altGlyph’ елемент, then the text string is ignored for the purposes of text layout; however, if ‘visibility’ is set to hidden, the text string is used for text layout (i.e., it takes up space) even though it is not rendered on the canvas. Regarding events, if ‘display’ is set to none, the елемент receives no events; however, if ‘visibility’ is set to hidden, the елемент might still receive events, depending on the value of властивість ‘pointer-events’. The geometry of a graphics елемент with ‘display’ set to none is not included in bounding box and clipping paths calculations; however, even if ‘visibility’ is to hidden, the geometry of the graphics елемент still contributes to bounding box and clipping path calculations.

‘display’

Value:	inline \| block \| list-item \| run-in \| compact \| marker \| table \| inline-table \| table-row-group \| table-header-group \| table-footer-group \| table-row \| table-column-group \| table-column \| table-cell \| table-caption \| none \| inherit
Initial:	inline
Applies to:	‘svg’, ‘g’, ‘switch’, ‘a’, ‘foreignObject’, graphics елементи (including the ‘text’ елемент) and text sub-елементи (i.e., ‘tspan’, ‘tref’, ‘altGlyph’, ‘textPath’)
Inherited:	no
Percentages:	N/A
Media:	all
Animatable:	yes

A value of display: none indicates that the given елемент and its children shall not be rendered directly (i.e., those елементи are not present in the rendering tree). Any value other than none or inherit indicates that the given елемент shall be rendered by the SVG user agent.

The ‘display’ властивість only affects the direct rendering of a given елемент, whereas it does not prevent елементи from being referenced by other елементи. For example, setting display: none on a ‘path’ елемент will prevent that елемент from getting rendered directly onto the canvas, but the ‘path’ елемент can still be referenced by a ‘textPath’ елемент; furthermore, its geometry will be used in text-on-a-path processing even if the ‘path’ has display: none.

The ‘display’ властивість affects direct rendering into offscreen canvases also, such as occurs with the implementation модель for masks. Thus, setting display: none on a child of a ‘mask’ will prevent the given child елемент from being rendered as part of the mask. Similarly, setting display: none on a child of a ‘clipPath’ елемент will prevent the given child елемент from contributing to the clipping path.

Elements with display: none do not take up space in text layout operations, do not receive events, and do not contribute to bounding box and clipping paths calculations.

Except for any additional information provided in this specification, the normative definition of the ‘display’ властивість is the CSS2 definition ([CSS2], section 9.2.6).

‘visibility’

Value:	visible \| hidden \| collapse \| inherit
Initial:	visible
Applies to:	graphics елементи (including the ‘text’ елемент) and text sub-елементи (i.e., ‘tspan’, ‘tref’, ‘altGlyph’, ‘textPath’ and ‘a’)
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

visible: The current graphics елемент is visible.
hidden or collapse: The current graphics елемент is invisible (i.e., nothing is painted on the canvas).

Note that if the ‘visibility’ властивість is set to hidden on a ‘tspan’, ‘tref’ or ‘altGlyph’ елемент, then the text is invisible but still takes up space in text layout calculations.

Depending on the value of властивість ‘pointer-events’, graphics елементи which have their ‘visibility’ властивість set to hidden still might receive events.

Except for any additional information provided in this specification, the normative definition of the ‘visibility’ властивість is the CSS2 definition ([CSS2], section 11.2).

11.6 Markers

11.6.1 Вступ

A marker is a symbol which is attached to one or more vertices of ‘path’, ‘line’, ‘polyline’ and ‘polygon’ елементи. Typically, markers are used to make arrowheads or polymarkers. Arrowheads can be defined by attaching a marker to the start or end vertices of ‘path’, ‘line’ or ‘polyline’ елементи. Polymarkers can be defined by attaching a marker to all vertices of a ‘path’, ‘line’, ‘polyline’ or ‘polygon’ елемент.

The graphics for a marker are defined by a ‘marker’ елемент. To indicate that a particular ‘marker’ елемент should be rendered at the vertices of a particular ‘path’, ‘line’, ‘polyline’ or ‘polygon’ елемент, set one or more marker властивості (‘marker’, ‘marker-start’, ‘marker-mid’ or ‘marker-end’) to reference the given ‘marker’ елемент.

Example Marker draws a triangular marker symbol as an arrowhead at the end of a path.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="4in" height="2in" 
     viewBox="0 0 4000 2000" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <defs>
    <marker id="Triangle"
      viewBox="0 0 10 10" refX="0" refY="5" 
      markerUnits="strokeWidth"
      markerWidth="4" markerHeight="3"
      orient="auto">
      <path d="M 0 0 L 10 5 L 0 10 z" />
    </marker>
  </defs>
  <rect x="10" y="10" width="3980" height="1980"
       fill="none" stroke="blue" stroke-width="10" />
  <desc>Placing an arrowhead at the end of a path.
  </desc>
  <path d="M 1000 750 L 2000 750 L 2500 1250"
        fill="none" stroke="black" stroke-width="100" 
        marker-end="url(#Triangle)"  />
</svg>

Example Marker

View this example as SVG (SVG-enabled browsers only)

Markers can be animated. The animated effects will show on all current uses of the markers within the document.

11.6.2 The ‘marker’ елемент

The ‘marker’ елемент defines the graphics that is to be used for drawing arrowheads or polymarkers on a given ‘path’, ‘line’, ‘polyline’ or ‘polygon’ елемент.

‘marker’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘viewBox’
‘preserveAspectRatio’
‘refX’
‘refY’
‘markerUnits’
‘markerWidth’
‘markerHeight’
‘orient’

DOM Інтерфейсs:

SVGMarkerElement

Attribute definitions:

markerUnits = "strokeWidth | userSpaceOnUse"

Defines the coordinate system for атрибути ‘markerWidth’, ‘markerHeight’ and the contents of the ‘marker’.
If markerUnits="strokeWidth", ‘markerWidth’, ‘markerHeight’ and the contents of the ‘marker’ represent values in a coordinate system which has a single unit equal the size in user units of the current stroke width (see the ‘stroke-width’ властивість) in place for the graphic object referencing the marker.
If markerUnits="userSpaceOnUse", ‘markerWidth’, ‘markerHeight’ and the contents of the ‘marker’ represent values in the current user coordinate system in place for the graphic object referencing the marker (i.e., the user coordinate system for the елемент referencing the ‘marker’ елемент via a ‘marker’, ‘marker-start’, ‘marker-mid’ or ‘marker-end’ властивість).
If атрибут ‘markerUnits’ is not specified, then the effect is as if a value of 'strokeWidth' were specified.
Animatable: yes.

refX = "<coordinate>"

The x-axis coordinate of the reference point which is to be aligned exactly at the marker position. The coordinate is defined in the coordinate system after application of the ‘viewBox’ and ‘preserveAspectRatio’ атрибути.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.

refY = "<coordinate>"

The y-axis coordinate of the reference point which is to be aligned exactly at the marker position. The coordinate is defined in the coordinate system after application of the ‘viewBox’ and ‘preserveAspectRatio’ атрибути.
If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes.

markerWidth = "<length>"

Represents the width of the viewport into which the marker is to be fitted when it is rendered.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
If the атрибут is not specified, the effect is as if a value of "3" were specified.
Animatable: yes.

markerHeight = "<length>"

Represents the height of the viewport into which the marker is to be fitted when it is rendered.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
If the атрибут is not specified, the effect is as if a value of "3" were specified.
Animatable: yes.

orient = "auto | <angle>"

Indicates how the marker is rotated.

A value of 'auto' indicates that the marker is oriented such that its positive x-axis is pointing as follows:

If there is a path segment coming into the vertex and another path segment going out of the vertex, the marker's positive x-axis should point toward the angle bisector for the angle at the given vertex, where that angle has one side consisting of tangent vector for the path segment going into the vertex and the other side the tangent vector for the path segment going out of the vertex. Note:
- If the tangent vectors are the same, the angle bisector equals the two tangent vectors.
- If an incoming and an outgoing vertex produce a zero vector the direction of marker is undefined.
If there is only a path segment going into the vertex (e.g., the last vertex on an open path), the marker's positive x-axis should point in the same direction as the tangent vector for the path segment going into the vertex.
If there is only a path segment going out of the vertex (e.g., the first vertex on an open path), the marker's positive x-axis should point in the same direction as the tangent vector for the path segment going out of the vertex. (Refer to ‘path’ елемент implementation notes for a more thorough discussion of the directionality of path segments.)

In all cases for closed subpaths (e.g., subpaths which end with a 'closepath' command), the orientation of the marker corresponding to the initial point of the subpath is calculated assuming that:

the path segment going into the vertex is the path segment corresponding to the closepath
the path segment coming out of the vertex is the first path segment in the subpath

When a 'closepath' command is followed by a command other than a 'moveto' command, then the orientation of the marker corresponding to the 'closepath' command is calculated assuming that:

the path segment going into the vertex is the path segment corresponding to the closepath
the path segment coming out of the vertex is the first path segment of the subsequent subpath

A <angle> value represents a particular orientation in the user space of the graphic object referencing the marker. For example, if a value of "0" is given, then the marker will be drawn such that its x-axis will align with the x-axis of the user space of the graphic object referencing the marker. If the атрибут is not specified, the effect is as if a value of "0" were specified.
Animatable: yes (non-additive).

Markers are drawn such that their reference point (i.e., атрибути ‘refX’ and ‘refY’) is positioned at the given vertex. In other words, a translation transformation is constructed by the user agent to achieve the effect of having point (‘refX’ and ‘refY’) within the marker content's coordinate system (after any transformations due to the ‘viewBox’ and ‘preserveAspectRatio’ атрибути) align exactly with the given vertex.

SVG's user agent style sheet sets the ‘overflow’ властивість for ‘marker’ елементи to hidden, which causes a rectangular clipping path to be created at the bounds of the marker tile. Unless the ‘overflow’ властивість is overridden, any graphics within the marker which goes outside of the marker rectangle will be clipped.

The contents of the ‘marker’ are relative to a new coordinate system. Attribute ‘markerUnits’ determines an initial scale factor for transforming the graphics in the marker into the user coordinate system for the referencing елемент. An additional set of transformations might occur if there is a ‘viewBox’ атрибут, in which case the coordinate system for the contents of the ‘marker’ will be transformed due to the processing of атрибути ‘viewBox’ and ‘preserveAspectRatio’. If there is no ‘viewBox’ атрибут, then the assumed default value for the the ‘viewBox’ атрибут has the origin of the viewBox coincident with the origin of the viewport and the width/height of the viewBox the same as the width/height of the viewport.

Properties inherit into the ‘marker’ елемент from its ancestors; властивості do not inherit from the елемент referencing the ‘marker’ елемент.

‘marker’ елементи are never rendered directly; their only usage is as something that can be referenced using the ‘marker’, ‘marker-start’, ‘marker-end’ and ‘marker-mid’ властивості. The ‘display’ властивість does not apply to the ‘marker’ елемент; thus, ‘marker’ елементи are not directly rendered even if the ‘display’ властивість is set to a value other than none, and ‘marker’ елементи are available for referencing even when the ‘display’ властивість on the ‘marker’ елемент or any of its ancestors is set to none.

Event атрибути and event listeners attached to the contents of a ‘marker’ елемент are not processed; only the rendering aspects of ‘marker’ елементи are processed.

11.6.3 Marker властивості

‘marker-start’ defines the arrowhead or polymarker that shall be drawn at the first vertex of the given ‘path’ елемент or basic shape. ‘marker-end’ defines the arrowhead or polymarker that shall be drawn at the final vertex. ‘marker-mid’ defines the arrowhead or polymarker that shall be drawn at every other vertex (i.e., every vertex except the first and last). Note that for a ‘path’ елемент which ends with a closed sub-path, the last vertex is the same as the initial vertex on the given sub-path. In this case, if ‘marker-end’ does not equal none, then it is possible that two markers will be rendered on the given vertex. One way to prevent this is to set ‘marker-end’ to none. (Note that the same comment applies to ‘polygon’ елементи.)

‘marker-start’

‘marker-mid’

‘marker-end’

Value:	none \| <funciri> \| inherit
Initial:	none
Applies to:	‘path’, ‘line’, ‘polyline’ and ‘polygon’ елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

none: Indicates that no marker symbol shall be drawn at the given vertex (vertices).
<funciri>: The <funciri> is a Functional IRI reference to the ‘marker’ елемент which shall be used as the arrowhead symbol or polymarker at the given vertex or vertices. If the IRI reference is not valid (e.g., it points to an object that is undefined or the object is not a ‘marker’ елемент), then the marker(s) shall not be drawn.

The ‘marker’ властивість specifies the marker symbol that shall be used for all points on the sets the value for all vertices on the given ‘path’ елемент or basic shape. It is a short-hand for the three individual marker властивості:

‘marker’

Value:	see individual властивості
Initial:	see individual властивості
Applies to:	‘path’, ‘line’, ‘polyline’ and ‘polygon’ елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

11.6.4 Details on how markers are rendered

Markers are drawn after the given object is filled and stroked.

For each marker that is drawn, a temporary new user coordinate system is established so that the marker will be positioned and sized correctly, as follows:

The axes of the temporary new user coordinate system are aligned according to the ‘orient’ атрибут on the ‘marker’ елемент and the slope of the curve at the given vertex. (Note: if there is a discontinuity at a vertex, the slope is the average of the slopes of the two segments of the curve that join at the given vertex. If a slope cannot be determined, the slope is assumed to be zero.)
A temporary new coordinate system is established by атрибут ‘markerUnits’. If ‘markerUnits’ equals 'strokeWidth', then the temporary new user coordinate system is the result of scaling the current user coordinate system by the current value of властивість ‘stroke-width’. If ‘markerUnits’ equals 'userSpaceOnUse', then no extra scale transformation is applied.
An additional set of transformations might occur if the ‘marker’ елемент includes a ‘viewBox’ атрибут, in which case additional transformations are set up to produce the necessary result due to атрибути ‘viewBox’ and ‘preserveAspectRatio’.
If the ‘overflow’ властивість on the ‘marker’ елемент indicates that the marker needs to be clipped to its viewport, then an implicit clipping path is established at the bounds of the viewport.

The rendering effect of a marker is as if the contents of the referenced ‘marker’ елемент were deeply cloned into a separate non-exposed DOM tree for each instance of the marker. Because the cloned DOM tree is non-exposed, the SVG DOM does not show the cloned instance of the marker.

For user agents that support Styling with CSS, the conceptual deep cloning of the referenced ‘marker’ елемент into a non-exposed DOM tree also copies any властивість values resulting from the CSS cascade ([CSS2], chapter 6) and властивість inheritance on the referenced елемент and its contents. CSS2 selectors can be applied to the original (i.e., referenced) елементи because they are part of the formal document structure. CSS2 selectors cannot be applied to the (conceptually) cloned DOM tree because its contents are not part of the formal document structure.

For illustrative purposes, we'll repeat the marker example shown earlier:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="4in" height="2in" 
     viewBox="0 0 4000 2000" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <defs>
    <marker id="Triangle"
      viewBox="0 0 10 10" refX="0" refY="5" 
      markerUnits="strokeWidth"
      markerWidth="4" markerHeight="3"
      orient="auto">
      <path d="M 0 0 L 10 5 L 0 10 z" />
    </marker>
  </defs>
  <rect x="10" y="10" width="3980" height="1980"
       fill="none" stroke="blue" stroke-width="10" />
  <desc>Placing an arrowhead at the end of a path.
  </desc>
  <path d="M 1000 750 L 2000 750 L 2500 1250"
        fill="none" stroke="black" stroke-width="100" 
        marker-end="url(#Triangle)"  />
</svg>

The rendering effect of the above file will be visually identical to the following:

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="4in" height="2in" 
     viewBox="0 0 4000 2000" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>File which produces the same effect
      as the marker example file, but without
      using markers.
  </desc>
  <rect x="10" y="10" width="3980" height="1980"
       fill="none" stroke="blue" stroke-width="10" />
  <!-- The path draws as before, but without the marker властивості -->
  <path d="M 1000 750 L 2000 750 L 2500 1250"
        fill="none" stroke="black" stroke-width="100"  />
  <!-- The following logic simulates drawing a marker 
       at final vertex of the path. -->
  <!-- First off, move the origin of the user coordinate system
       so that the origin is now aligned with the end point of the path. -->
  <g transform="translate(2500,1250)" >
    <!-- Rotate the coordinate system 45 degrees because
         the marker specified orient="auto" and the final segment
         of the path is going in the direction of 45 degrees. -->
    <g transform="rotate(45)" >
      <!-- Scale the coordinate system to match the coordinate system
           indicated by the 'markerUnits' атрибути, which in this case has
           a value of 'strokeWidth'. Therefore, scale the coordinate system
           by the current value of the 'stroke-width' властивість, which is 100. -->
      <g transform="scale(100)" >
        <!-- Translate the coordinate system by 
             (-refX*viewBoxToMarkerUnitsScaleX, -refY*viewBoxToMarkerUnitsScaleY)
             in order that (refX,refY) within the marker will align with the vertex.
             In this case, we use the default value for preserveAspectRatio
             ('xMidYMid meet'), which means find a uniform scale factor
             (i.e., viewBoxToMarkerUnitsScaleX=viewBoxToMarkerUnitsScaleY)
             such that the viewBox fits entirely within the viewport ('meet') and 
             is center-aligned ('xMidYMid'). In this case, the uniform scale factor
             is markerHeight/viewBoxHeight=3/10=.3. Therefore, translate by
             (-refX*.3,-refY*.3)=(0*.3,-5*.3)=(0,-1.5). -->
        <g transform="translate(0,-1.5)" >
          <!-- There is an implicit clipping path because the user agent style
               sheet says that the 'overflow' властивість for markers has the value
               'hidden'. To achieve this, create a clipping path at the bounds
               of the viewport. Note that in this case the viewport extends
               0.5 units to the left and right of the viewBox due to 
               a uniform scale factor, different ratios for markerWidth/viewBoxWidth
               and markerHeight/viewBoxHeight, and 'xMidYMid' alignment -->
          <clipPath id="cp1" >
            <rect x="-0.5" y="0" width="4" height="3" />
          </clipPath>
          <g clip-path="url(#cp1)" >
            <!-- Scale the coordinate system by the uniform scale factor
                 markerHeight/viewBoxHeight=3/10=.3 to set the coordinate
                 system to viewBox units. -->
            <g transform="scale(.3)" >
              <!-- This 'g' елемент carries all властивість values that result from
                   cascading and inheritance of властивості on the original 'marker' елемент.
                   In this example, neither fill nor stroke was specified on the 'marker'
                   елемент or any ancestors of the 'marker', so the initial values of
                   "black" and "none" are used, respectively. -->
             <g fill="black" stroke="none" >
                <!-- Expand out the contents of the 'marker' елемент. -->
                <path d="M 0 0 L 10 5 L 0 10 z" />
              </g>
            </g>
          </g>
        </g>
      </g>
    </g>
  </g>
</svg>

11.7 Rendering властивості

11.7.1 Color interpolation властивості: ‘color-interpolation’ and ‘color-interpolation-filters’

The SVG user agent performs color interpolations and compositing at various points as it processes SVG content. Two властивості, ‘color-interpolation’ and ‘color-interpolation-filters’, control which color space is used for particular categories of graphics operations. The following table shows which властивість applies to which graphics operations:

Graphics operation	Corresponding властивість
interpolating between gradient stops (see Gradient)	‘color-interpolation’
interpolating color when performing color animations with either ‘animate’ or ‘animateColor’	‘color-interpolation’
alpha compositing of graphics елементи into the current background	‘color-interpolation’
filter effects	‘color-interpolation-filters’

Both властивості choose between color operations occurring in the sRGB color space or in a (light energy linear) linearized RGB color space. Having chosen the appropriate color space, component-wise linear interpolation is used.

The conversion formulas between the sRGB color space (i.e., nonlinear with 2.2 gamma curve) and the linearized RGB color space (i.e., color values expressed as sRGB tristimulus values without a gamma curve) can be found in the sRGB specification [SRGB]. For illustrative purposes, the following formula shows the conversion from sRGB to linearized RGB:

  R[sRGB] = R[sRGB-8bit] / 255
  G[sRGB] = G[sRGB-8bit] / 255
  B[sRGB] = B[sRGB-8bit] / 255
If R[sRGB], G[sRGB], B[sRGB] <= 0.04045
  R[linearRGB] = R[sRGB] / 12.92
  G[linearRGB] = G[sRGB] / 12.92
  B[linearRGB] = B[sRGB] / 12.92
else if R[sRGB], G[sRGB], B[sRGB] > 0.04045
  R[linearRGB] = ((R[sRGB] + 0.055) / 1.055) ^ 2.4
  G[linearRGB] = ((G[sRGB] + 0.055) / 1.055) ^ 2.4
  B[linearRGB] = ((B[sRGB] + 0.055) / 1.055) ^ 2.4
  R[linearRGB-8bit] = R[linearRGB] * 255
  G[linearRGB-8bit] = G[linearRGB] * 255
  B[linearRGB-8bit] = B[linearRGB] * 255

Out-of-range color values, if supported by the user agent, also are converted using the above formulas. (See Clamping values which are restricted to a particular range.)

‘color-interpolation’

Value:	auto \| sRGB \| linearRGB \| inherit
Initial:	sRGB
Applies to:	container елементи, graphics елементи, ‘animate’ and ‘animateColor’
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

auto: Indicates that the user agent can choose either the sRGB or linearRGB spaces for color interpolation. This option indicates that the author doesn't require that color interpolation occur in a particular color space.
sRGB: Indicates that color interpolation should occur in the sRGB color space.
linearRGB: Indicates that color interpolation should occur in the linearized RGB color space as described above.

The ‘color-interpolation’ властивість specifies the color space for gradient interpolations, color animations and alpha compositing.

When a child елемент is blended into a background, the value of the ‘color-interpolation’ властивість on the child determines the type of blending, not the value of the ‘color-interpolation’ on the parent. For gradients which make use of the ‘xlink:href’ атрибут to reference another gradient, the gradient uses the ‘color-interpolation’ властивість value from the gradient елемент which is directly referenced by the ‘fill’ or ‘stroke’ властивість. When animating colors, color interpolation is performed according to the value of the ‘color-interpolation’ властивість on the елемент being animated.

‘color-interpolation-filters’

Value:	auto \| sRGB \| linearRGB \| inherit
Initial:	linearRGB
Applies to:	filter primitives
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

auto: Indicates that the user agent can choose either the sRGB or linearRGB spaces for filter effects color operations. This option indicates that the author doesn't require that color operations occur in a particular color space.
sRGB: Indicates that filter effects color operations should occur in the sRGB color space.
linearRGB: Indicates that filter effects color operations should occur in the linearized RGB color space.

The ‘color-interpolation-filters’ властивість specifies the color space for imaging operations performed via filter effects.

Note that ‘color-interpolation-filters’ has a different initial value than ‘color-interpolation’. ‘color-interpolation-filters’ has an initial value of linearRGB, whereas ‘color-interpolation’ has an initial value of sRGB. Thus, in the default case, filter effects operations occur in the linearRGB color space, whereas all other color interpolations occur by default in the sRGB color space.

11.7.2 The ‘color-rendering’ властивість

The creator of SVG content might want to provide a hint to the implementation about how to make speed vs. quality tradeoffs as it performs color interpolation and compositing. The ‘color-rendering’ властивість provides a hint to the SVG user agent about how to optimize its color interpolation and compositing operations.

‘color-rendering’ takes precedence over ‘color-interpolation-filters’. For example, assume color-rendering: optimizeSpeed and color-interpolation-filters: linearRGB. In this case, the SVG user agent should perform color operations in a way that optimizes performance, which might mean sacrificing the color interpolation precision as specified by color-interpolation-filters: linearRGB.

‘color-rendering’

Value:	auto \| optimizeSpeed \| optimizeQuality \| inherit
Initial:	auto
Applies to:	container елементи, graphics елементи, ‘animate’ and ‘animateColor’
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

auto: Indicates that the user agent shall make appropriate tradeoffs to balance speed and quality, but quality shall be given more importance than speed.
optimizeSpeed: Indicates that the user agent shall emphasize rendering speed over quality. For RGB display devices, this option will sometimes cause the user agent to perform color interpolation and compositing in the device RGB color space.
optimizeQuality: Indicates that the user agent shall emphasize quality over rendering speed.

11.7.3 The ‘shape-rendering’ властивість

The creator of SVG content might want to provide a hint to the implementation about what tradeoffs to make as it renders vector graphics елементи such as ‘path’ елементи and basic shapes such as circles and rectangles. The ‘shape-rendering’ властивість provides these hints.

‘shape-rendering’

Value:	auto \| optimizeSpeed \| crispEdges \| geometricPrecision \| inherit
Initial:	auto
Applies to:	shapes
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

auto: Indicates that the user agent shall make appropriate tradeoffs to balance speed, crisp edges and geometric precision, but with geometric precision given more importance than speed and crisp edges.
optimizeSpeed: Indicates that the user agent shall emphasize rendering speed over geometric precision and crisp edges. This option will sometimes cause the user agent to turn off shape anti-aliasing.
crispEdges: Indicates that the user agent shall attempt to emphasize the contrast between clean edges of artwork over rendering speed and geometric precision. To achieve crisp edges, the user agent might turn off anti-aliasing for all lines and curves or possibly just for straight lines which are close to vertical or horizontal. Also, the user agent might adjust line positions and line widths to align edges with device pixels.
geometricPrecision: Indicates that the user agent shall emphasize geometric precision over speed and crisp edges.

11.7.4 The ‘text-rendering’ властивість

The creator of SVG content might want to provide a hint to the implementation about what tradeoffs to make as it renders text. The ‘text-rendering’ властивість provides these hints.

‘text-rendering’

Value:	auto \| optimizeSpeed \| optimizeLegibility \| geometricPrecision \| inherit
Initial:	auto
Applies to:	‘text’ елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

auto: Indicates that the user agent shall make appropriate tradeoffs to balance speed, legibility and geometric precision, but with legibility given more importance than speed and geometric precision.
optimizeSpeed: Indicates that the user agent shall emphasize rendering speed over legibility and geometric precision. This option will sometimes cause the user agent to turn off text anti-aliasing.
optimizeLegibility: Indicates that the user agent shall emphasize legibility over rendering speed and geometric precision. The user agent will often choose whether to apply anti-aliasing techniques, built-in font hinting or both to produce the most legible text.
geometricPrecision: Indicates that the user agent shall emphasize geometric precision over legibility and rendering speed. This option will usually cause the user agent to suspend the use of hinting so that glyph outlines are drawn with comparable geometric precision to the rendering of path data.

11.7.5 The ‘image-rendering’ властивість

The creator of SVG content might want to provide a hint to the implementation about how to make speed vs. quality tradeoffs as it performs image processing. The ‘image-rendering’ властивість provides a hint to the SVG user agent about how to optimize its image rendering.

‘image-rendering’

Value:	auto \| optimizeSpeed \| optimizeQuality \| inherit
Initial:	auto
Applies to:	images
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

auto: Indicates that the user agent shall make appropriate tradeoffs to balance speed and quality, but quality shall be given more importance than speed. The user agent shall employ a resampling algorithm at least as good as nearest neighbor resampling, but bilinear resampling is strongly preferred. For Conforming High-Quality SVG Viewers, the user agent shall employ a resampling algorithm at least as good as bilinear resampling.
optimizeQuality: Indicates that the user agent shall emphasize quality over rendering speed. The user agent shall employ a resampling algorithm at least as good as bilinear resampling.
optimizeSpeed: Indicates that the user agent shall emphasize rendering speed over quality. The user agent should use a resampling algorithm which achieves the goal of fast rendering, with the requirement that the resampling algorithm shall be at least as good as nearest neighbor resampling. If performance goals can be achieved with higher quality algorithms, then the user agent should use the higher quality algorithms instead of nearest neighbor resampling.

In all cases, resampling must be done in a truecolor (e.g., 24-bit) color space even if the original data and/or the target device is indexed color.

11.8 Inheritance of painting властивості

The values of any of the painting властивості described in this chapter can be inherited from a given object's parent. Painting, however, is always done on each graphics елемент individually, never at the container елемент (e.g., a ‘g’) level. Thus, for the following SVG, even though the gradient fill is specified on the ‘g’, the gradient is simply inherited through the ‘g’ елемент down into each rectangle, each of which is rendered such that its interior is painted with the gradient.

Example Inheritance

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="7cm" height="2cm" viewBox="0 0 700 200"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Gradients apply to leaf nodes
  </desc>
  <g>
    <defs>
      <linearGradient id="MyGradient" gradientUnits="objectBoundingBox">
        <stop offset="0%" stop-color="#F60" />
        <stop offset="100%" stop-color="#FF6" />
      </linearGradient>
    </defs>
    <rect x="1" y="1" width="698" height="198"
          fill="none" stroke="blue" stroke-width="2" />
    <g fill="url(#MyGradient)" >
      <rect x="100" y="50" width="200" height="100"/>
      <rect x="400" y="50" width="200" height="100"/>
   </g>
  </g>
</svg>

Example Inheritance

View this example as SVG (SVG-enabled browsers only)

Any painting властивості defined in terms of the object's bounding box use the bounding box of the graphics елемент to which the operation applies. Note that text елементи are defined such that any painting operations defined in terms of the object's bounding box use the bounding box of the entire ‘text’ елемент. (See the discussion of object bounding box units and text елементи.)

11.9 DOM interfaces

11.9.1 Інтерфейс SVGPaint

The SVGPaint interface corresponds to basic type <paint> and represents the values of властивості ‘fill’ and ‘stroke’.

Note: The SVGPaint interface is deprecated, and may be dropped from future versions of the SVG specification.

interface SVGPaint : SVGColor {

  // Paint Types
  const unsigned short SVG_PAINTTYPE_UNKNOWN = 0;
  const unsigned short SVG_PAINTTYPE_RGBCOLOR = 1;
  const unsigned short SVG_PAINTTYPE_RGBCOLOR_ICCCOLOR = 2;
  const unsigned short SVG_PAINTTYPE_NONE = 101;
  const unsigned short SVG_PAINTTYPE_CURRENTCOLOR = 102;
  const unsigned short SVG_PAINTTYPE_URI_NONE = 103;
  const unsigned short SVG_PAINTTYPE_URI_CURRENTCOLOR = 104;
  const unsigned short SVG_PAINTTYPE_URI_RGBCOLOR = 105;
  const unsigned short SVG_PAINTTYPE_URI_RGBCOLOR_ICCCOLOR = 106;
  const unsigned short SVG_PAINTTYPE_URI = 107;

  readonly атрибут unsigned short paintType;
  readonly атрибут DOMString uri;

  void setUri(in DOMString uri);
  void setPaint(in unsigned short paintType, in DOMString uri, in DOMString rgbColor, in DOMString iccColor) raises(SVGException);
};

Constants in group “Paint Types”:

SVG_PAINTTYPE_UNKNOWN (unsigned short): The paint type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_PAINTTYPE_RGBCOLOR (unsigned short): An sRGB color has been specified without an alternative ICC color specification.
SVG_PAINTTYPE_RGBCOLOR_ICCCOLOR (unsigned short): An sRGB color has been specified along with an alternative ICC color specification.
SVG_PAINTTYPE_NONE (unsigned short): Corresponds to a none value on a <paint> specification.
SVG_PAINTTYPE_CURRENTCOLOR (unsigned short): Corresponds to a currentColor value on a <paint> specification.
SVG_PAINTTYPE_URI_NONE (unsigned short): A URI has been specified, along with an explicit none as the backup paint method in case the URI is unavailable or invalid.
SVG_PAINTTYPE_URI_CURRENTCOLOR (unsigned short): A URI has been specified, along with an sRGB color as the backup paint method in case the URI is unavailable or invalid.
SVG_PAINTTYPE_URI_RGBCOLOR (unsigned short): A URI has been specified, along with an sRGB color as the backup paint method in case the URI is unavailable or invalid.
SVG_PAINTTYPE_URI_RGBCOLOR_ICCCOLOR (unsigned short): A URI has been specified, along with both an sRGB color and alternate ICC color as the backup paint method in case the URI is unavailable or invalid.
SVG_PAINTTYPE_URI (unsigned short): Only a URI has been specified.

Attributes:

paintType (readonly unsigned short): The type of paint, identified by one of the SVG_PAINTTYPE_* constants defined on this interface.
uri (readonly DOMString): When the paintType specifies a URI, this атрибут holds the URI string. When the paintType does not specify a URI, this атрибут is null.

Operations:

void setUri(in DOMString uri)

Sets the paintType to SVG_PAINTTYPE_URI_NONE and sets uri to the specified value.

Parameters

DOMString uri

The URI for the desired paint server.

void setPaint(in unsigned short paintType, in DOMString uri, in DOMString rgbColor, in DOMString iccColor)

Sets the paint as specified by the parameters. If paintType requires a URI, then uri must be non-null; otherwise, uri must be null. If paintType requires an RGBColor, then rgbColor must be a string that matches <color>; otherwise, rgbColor must be null. If paintType requires an SVGICCColor, then iccColor must be a string that matches <icccolor>; otherwise, iccColor must be null.

Parameters

unsigned short paintType

One of the defined constants for paintType.
DOMString uri

The URI for the desired paint server, or null.
DOMString rgbColor

The specification of an sRGB color, or null.
DOMString iccColor

The specification of an ICC color, or null.

Exceptions

SVGException, code SVG_INVALID_VALUE_ERR: Raised if one of the parameters has an invalid value.

11.9.2 Інтерфейс SVGMarkerElement

The SVGMarkerElement interface corresponds to the ‘marker’ елемент.

interface SVGMarkerElement : SVGElement,
                             SVGLangSpace,
                             SVGExternalResourcesRequired,
                             SVGStylable,
                             SVGFitToViewBox {

  // Marker Unit Types
  const unsigned short SVG_MARKERUNITS_UNKNOWN = 0;
  const unsigned short SVG_MARKERUNITS_USERSPACEONUSE = 1;
  const unsigned short SVG_MARKERUNITS_STROKEWIDTH = 2;

  // Marker Orientation Types
  const unsigned short SVG_MARKER_ORIENT_UNKNOWN = 0;
  const unsigned short SVG_MARKER_ORIENT_AUTO = 1;
  const unsigned short SVG_MARKER_ORIENT_ANGLE = 2;

  readonly атрибут SVGAnimatedLength refX;
  readonly атрибут SVGAnimatedLength refY;
  readonly атрибут SVGAnimatedEnumeration markerUnits;
  readonly атрибут SVGAnimatedLength markerWidth;
  readonly атрибут SVGAnimatedLength markerHeight;
  readonly атрибут SVGAnimatedEnumeration orientType;
  readonly атрибут SVGAnimatedAngle orientAngle;

  void setOrientToAuto() raises(DOMException);
  void setOrientToAngle(in SVGAngle angle) raises(DOMException);
};

Constants in group “Marker Unit Types”:

SVG_MARKERUNITS_UNKNOWN (unsigned short): The marker unit type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_MARKERUNITS_USERSPACEONUSE (unsigned short): The value of атрибут ‘markerUnits’ is 'userSpaceOnUse'.
SVG_MARKERUNITS_STROKEWIDTH (unsigned short): The value of атрибут ‘markerUnits’ is 'strokeWidth'.

Constants in group “Marker Orientation Types”:

SVG_MARKER_ORIENT_UNKNOWN (unsigned short): The marker orientation is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_MARKER_ORIENT_AUTO (unsigned short): Attribute ‘orient’ has value 'auto'.
SVG_MARKER_ORIENT_ANGLE (unsigned short): Attribute ‘orient’ has an angle value.

Attributes:

refX (readonly SVGAnimatedLength): Corresponds to атрибут ‘refX’ on the given ‘marker’ елемент.
refY (readonly SVGAnimatedLength): Corresponds to атрибут ‘refY’ on the given ‘marker’ елемент.
markerUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘markerUnits’ on the given ‘marker’ елемент. One of the Marker Unit Types defined on this interface.
markerWidth (readonly SVGAnimatedLength): Corresponds to атрибут ‘markerWidth’ on the given ‘marker’ елемент.
markerHeight (readonly SVGAnimatedLength): Corresponds to атрибут ‘markerHeight’ on the given ‘marker’ елемент.
orientType (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘orient’ on the given ‘marker’ елемент. One of the Marker Orientation Types defined on this interface.
orientAngle (readonly SVGAnimatedAngle): Corresponds to атрибут ‘orient’ on the given ‘marker’ елемент. If markerUnits is SVG_MARKER_ORIENT_ANGLE, the angle value for атрибут ‘orient’; otherwise, it will be set to zero.

Operations:

void setOrientToAuto()

Sets the value of атрибут ‘orient’ to 'auto'.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

void setOrientToAngle(in SVGAngle angle)

Sets the value of атрибут ‘orient’ to the given angle.

Parameters

SVGAngle angle

The angle value to use for атрибут ‘orient’.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

12 Color

12.1 Вступ
12.2 The ‘color’ властивість
12.3 Color profile descriptions
12.4 DOM interfaces
- 12.4.1 Інтерфейс SVGColorProfileElement
- 12.4.2 Інтерфейс SVGColorProfileRule

12.1 Вступ

All SVG colors are specified in the sRGB color space [SRGB]. At a minimum, SVG user agents shall conform to the color behavior requirements specified in the color units section and the minimal gamma correction rules defined in the CSS2 specification.

Additionally, SVG content can specify an alternate color specification using an ICC profile [ICC42] as described in Specifying paint. If ICC-based colors are provided and the SVG user agent supports ICC color, then the ICC-based color takes precedence over the sRGB color specification; otherwise, the RGB fallback colors must be used. Note that, in this specification, color interpolation occurs in an RGB color space even if an ICC-based color specification is provided (see ‘color-interpolation’).

12.2 The ‘color’ властивість

The ‘color’ властивість is used to provide a potential indirect value (currentColor) for the ‘fill’, ‘stroke’, ‘stop-color’, ‘flood-color’ and ‘lighting-color’ властивості.

‘color’

Value:	<color> \| inherit
Initial:	depends on user agent
Applies to:	елементи to which властивості ‘fill’, ‘stroke’, ‘stop-color’, ‘flood-color’ and ‘lighting-color’ apply
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

Except for any additional information provided in this specification, the normative definition of the властивість is in CSS2 ([CSS2], section 14.1).

12.3 Color profile descriptions

12.3.1 Огляд of color profile descriptions

The International Color Consortium has established a standard, the ICC Profile [ICC42], for documenting the color characteristics of input and output devices. Using these profiles, it is possible to build a transform and correct visual data for viewing on different devices.

A color profile description provides the bridge between an ICC profile and references to that ICC profile within SVG content. The color profile description is added to the user agent's list of known color profiles and then used to select the relevant profile. The color profile description contains descriptors for the location of the color profile on the Web, a name to reference the profile and information about rendering intent.

12.3.2 Alternative ways of defining a color profile description

Color profile descriptions can be specified in either of the following ways:

a ‘color-profile’ елемент
an @color-profile rule within a CSS style sheet (only applicable for user agents which support using CSS to style the SVG content [CSS2])

If a color profile with the same name value has been identified by both a ‘color-profile’ елемент and @color-profile rules within a CSS style sheet, then the user agent shall first attempt to locate the profile by using the specifications in the @color-profile rules first.

12.3.3 The ‘color-profile’ елемент

‘color-profile’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘local’
‘name’
‘rendering-intent’
‘xlink:href’

DOM Інтерфейсs:

SVGColorProfileElement

Attribute definitions:

xlink:href = "<iri>"

The location of an ICC profile resource.
Animatable: no.

local = "<string>"

The unique ID for a locally stored color profile. <string> is the profile's unique ID as specified by International Color Consortium. If both the ‘xlink:href’ and the ‘local’ атрибути are specified, then the user agent shall search the local system for the locally stored color profile first, and, if not available locally, then attempt to use the resource identified by the ‘xlink:href’ атрибут. (Note: Profile description fields do not represent a profile's unique ID. With current ICC proposals, the profile's unique ID is an MD5-encoded value within the profile header.)
Animatable: no.

name = "<name>"

The name which is used as the first parameter for icc-color specifications within ‘fill’, ‘stroke’, ‘stop-color’, ‘flood-color’ and ‘lighting-color’ властивість values to identify the color profile to use for the ICC color specification and the name which can be the value of the ‘color-profile’ властивість. Note that if <name> is not provided, it will be impossible to reference the given color profile description. The name "sRGB" is predefined; any color profile descriptions with <name> set to "sRGB" will be ignored. For consistency with CSS lexical scanning and parsing rules ([CSS2], section D.2), the keyword "sRGB" is case-insensitive; however, it is recommended that the mixed capitalization "sRGB" be used for consistency with common industry practice.
Animatable: no.

rendering-intent = "auto | perceptual | relative-colorimetric | saturation | absolute-colorimetric"

‘rendering-intent’ permits the specification of a color profile rendering intent other than the default. ‘rendering-intent’ is applicable primarily to color profiles corresponding to CMYK color spaces. The different options cause different methods to be used for translating colors to the color gamut of the target rendering device:

auto: This is the default behavior. The user agent determines the best intent based on the content type. For image content containing an embedded profile, it shall be assumed that the intent specified within the profile is the desired intent. Otherwise, the user agent shall use the current profile and force the intent, overriding any intent that might be stored in the profile itself.
perceptual: This method, often the preferred choice for images, preserves the relationship between colors. It attempts to maintain relative color values among the pixels as they are mapped to the target device gamut. Sometimes pixel values that were originally within the target device gamut are changed in order to avoid hue shifts and discontinuities and to preserve as much as possible the overall appearance of the scene.
saturation: Preserves the relative saturation (chroma) values of the original pixels. Out of gamut colors are converted to colors that have the same saturation but fall just inside the gamut.
relative-colorimetric: Leaves colors that fall inside the gamut unchanged. This method usually converts out of gamut colors to colors that have the same lightness but fall just inside the gamut.
absolute-colorimetric: Disables white point matching when converting colors. This option is generally not recommended.

Animatable: no.

12.3.4 The CSS @color-profile rule

When the document is styled using CSS, the @color-profile rule can be used to specify a color profile description. The general form is:

@color-profile { <color-profile-description> }

where the <color-profile-description> has the form:

descriptor: value;
[...]
descriptor: value;

Each @color-profile rule specifies a value for every color profile descriptor, either implicitly or explicitly. Those not given explicit values in the rule take the initial value listed with each descriptor in this specification. These descriptors apply solely within the context of the @color-profile rule in which they are defined, and do not apply to document language елементи. Thus, there is no notion of which елементи the descriptors apply to, or whether the values are inherited by child елементи.

The following are the descriptors for a <color-profile-description>:

‘src’

Values:	sRGB \| <local-profile> \| <iri> \| (<local-profile> <iri>) \| inherit
Initial:	sRGB
Media:	visual

sRGB

The source profile is the sRGB color space. For consistency with CSS lexical scanning and parsing rules ([CSS2], section D.2), the keyword "sRGB" is case-insensitive; however, it is recommended that the mixed capitalization "sRGB" be used for consistency with common industry practice.

<local-profile>

The source profile is a locally-stored profile. The syntax for <local-profile> is:

"local(" + <string> + ")"

where <string> is the profile's unique ID as specified by International Color Consortium. (Note: Profile description fields do not represent a profile's unique ID. With current ICC proposals, the profile's unique ID is an MD5-encoded value within the profile header.)

<iri>

The source profile is a IRI reference to a color profile.

(<local-profile> <iri>)

Two profiles are specified. If <local-profile> cannot be found on the local system, then the <iri> is used.

‘name’

Values:	<name>
Initial:	undefined
Media:	visual

<name>: See the description for the ‘name’ атрибут on the ‘color-profile’ елемент. Note that if <name> is not provided, it will be impossible to reference the given @color-profile definition.

‘rendering-intent’

Values:	auto \| perceptual \| relative-colorimetric \| saturation \| absolute-colorimetric
Initial:	auto
Media:	visual
Animatable:	no

See the description for the ‘rendering-intent’ атрибут on the ‘color-profile’ елемент.

12.3.5 The ‘color-profile’ властивість

‘color-profile’

Value:	auto \| sRGB \| <name> \| <iri> \| inherit
Initial:	auto
Applies to:	‘image’ елементи that refer to raster images
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

auto: This is the default behavior. All colors are presumed to be defined in the sRGB color space unless a more precise embedded profile is specified within content data. For images that do have a profile built into their data, that profile is used. For images that do not have a profile, the sRGB profile is used.
sRGB: The source profile is assumed to be sRGB. This differs from auto in that it overrides an embedded profile inside an image.

For consistency with CSS lexical scanning and parsing rules ([CSS2], section D.2), the keyword "sRGB" is case-insensitive; however, it is recommended that the mixed capitalization "sRGB" be used for consistency with common industry practice.
<name>: A name corresponding to a defined color profile that is in the user agent's color profile description database. The user agent searches the color profile description database for a color profile description entry whose name descriptor matches <name> and uses the last matching entry that is found. If a match is found, the corresponding profile overrides an embedded profile inside an image. If no match is found, then the embedded profile inside the image is used.
<iri>: A IRI reference to the source color profile. The referenced color profile overrides an embedded profile inside the image.

12.4 DOM interfaces

12.4.1 Інтерфейс SVGColorProfileElement

The SVGColorProfileElement interface corresponds to the ‘color-profile’ елемент.

interface SVGColorProfileElement : SVGElement,
                                   SVGURIReference,
                                   SVGRenderingIntent {
  атрибут DOMString local;
  атрибут DOMString name;
  атрибут unsigned short renderingIntent;
};

Attributes:

local (DOMString): Corresponds to атрибут ‘local’ on the given елемент.
name (DOMString): Corresponds to атрибут ‘name’ on the given елемент.
renderingIntent (unsigned short): Corresponds to атрибут ‘rendering-intent’ on the given елемент. The value of this атрибут is the value of the the RENDERING_INTENT_* constant defined on SVGRenderingIntent that corresponds to the value of the ‘rendering-intent’ атрибут.

12.4.2 Інтерфейс SVGColorProfileRule

The SVGColorProfileRule interface represents an @color-profile rule in a CSS style sheet. An @color-profile rule identifies a ICC profile which can be referenced within a given document.

Support for the SVGColorProfileRule interface is only required in user agents that support styling with CSS.

interface SVGColorProfileRule : SVGCSSRule,
                                SVGRenderingIntent {
  атрибут DOMString src setraises(DOMException);
  атрибут DOMString name setraises(DOMException);
  атрибут unsigned short renderingIntent setraises(DOMException);
};

Attributes:

src (DOMString)

Corresponds to descriptor src within an @color-profile rule.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

name (DOMString)

Corresponds to descriptor ‘name’ within an @color-profile rule.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

renderingIntent (unsigned short)

The type of rendering intent, identified by one of the SVGRenderingIntent constants.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

13 Gradients and Patterns

13.1 Вступ
13.2 Gradients
13.3 Patterns
13.4 DOM interfaces

13.1 Вступ

With SVG, you can fill (i.e., paint the interior) or stroke (i.e., paint the outline) of shapes and text using one of the following:

color (using <color>)
gradients (linear or radial)
patterns (vector or image, possibly tiled)

SVG uses the general notion of a paint server. Gradients and patterns are just specific types of built-in paint servers.

Paint servers are referenced using an IRI reference on a ‘fill’ or ‘stroke’ властивість.

13.2 Gradients

13.2.1 Вступ

Gradients consist of continuously smooth color transitions along a vector from one color to another, possibly followed by additional transitions along the same vector to other colors. SVG provides for two types of gradients: linear gradients and radial gradients.

Once defined, gradients are then referenced using ‘fill’ or ‘stroke’ властивості on a given graphics елемент to indicate that the given елемент shall be filled or stroked with the referenced gradient.

The angle of the color transitions along the gradient vector is defined by the gradient normal. Before any transforms are applied to the gradient or its referencing graphics елемент, the gradient normal is perpendicular with the gradient vector. If a graphics елемент references a gradient, conceptually the graphics елемент should take a copy of the gradient vector and gradient normal and treat it as part of its own geometry. Any transformations applied to the graphics елемент geometry also apply to the copied gradient vector and gradient normal. Any gradient transforms that are specified on the reference gradient are applied before any graphics елемент transformations are applied to the gradient.

linear and radial gradient vectors and normals

13.2.2 Linear gradients

Linear gradients are defined by a ‘linearGradient’ елемент.

‘linearGradient’

Categories:

Gradient елемент

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’
‘animate’
‘animateTransform’
‘set’
‘stop’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘x1’
‘y1’
‘x2’
‘y2’
‘gradientUnits’
‘gradientTransform’
‘spreadMethod’
‘xlink:href’

DOM Інтерфейсs:

SVGLinearGradientElement

Attribute definitions:

gradientUnits = "userSpaceOnUse | objectBoundingBox": Defines the coordinate system for атрибути ‘x1’, ‘y1’, ‘x2’ and ‘y2’.
If gradientUnits="userSpaceOnUse", ‘x1’, ‘y1’, ‘x2’ and ‘y2’ represent values in the coordinate system that results from taking the current user coordinate system in place at the time when the gradient елемент is referenced (i.e., the user coordinate system for the елемент referencing the gradient елемент via a ‘fill’ or ‘stroke’ властивість) and then applying the transform specified by атрибут ‘gradientTransform’.
If gradientUnits="objectBoundingBox", the user coordinate system for атрибути ‘x1’, ‘y1’, ‘x2’ and ‘y2’ is established using the bounding box of the елемент to which the gradient is applied (see Object bounding box units) and then applying the transform specified by атрибут ‘gradientTransform’.
When gradientUnits="objectBoundingBox" and ‘gradientTransform’ is the identity matrix, the normal of the linear gradient is perpendicular to the gradient vector in object bounding box space (i.e., the abstract coordinate system where (0,0) is at the top/left of the object bounding box and (1,1) is at the bottom/right of the object bounding box). When the object's bounding box is not square, the gradient normal which is initially perpendicular to the gradient vector within object bounding box space may render non-perpendicular relative to the gradient vector in user space. If the gradient vector is parallel to one of the axes of the bounding box, the gradient normal will remain perpendicular. This transformation is due to application of the non-uniform scaling transformation from bounding box space to user space.
If атрибут ‘gradientUnits’ is not specified, then the effect is as if a value of 'objectBoundingBox' were specified.
Animatable: yes.
gradientTransform = "<transform-list>": Contains the definition of an optional additional transformation from the gradient coordinate system onto the target coordinate system (i.e., userSpaceOnUse or objectBoundingBox). This allows for things such as skewing the gradient. This additional transformation matrix is post-multiplied to (i.e., inserted to the right of) any previously defined transformations, including the implicit transformation necessary to convert from object bounding box units to user space.
If атрибут ‘gradientTransform’ is not specified, then the effect is as if an identity transform were specified.
Animatable: yes.
x1 = "<coordinate>": ‘x1’, ‘y1’, ‘x2’ and ‘y2’ define a gradient vector for the linear gradient. This gradient vector provides starting and ending points onto which the gradient stops are mapped. The values of ‘x1’, ‘y1’, ‘x2’ and ‘y2’ can be either numbers or percentages.
If the атрибут is not specified, the effect is as if a value of '0%' were specified.
Animatable: yes.
y1 = "<coordinate>": See ‘x1’.
If the атрибут is not specified, the effect is as if a value of '0%' were specified.
Animatable: yes.
x2 = "<coordinate>": See ‘x1’.
If the атрибут is not specified, the effect is as if a value of '100%' were specified.
Animatable: yes.
y2 = "<coordinate>": See ‘x1’.
If the атрибут is not specified, the effect is as if a value of '0%' were specified.
Animatable: yes.
spreadMethod = "pad | reflect | repeat": Indicates what happens if the gradient starts or ends inside the bounds of the target rectangle. Possible values are: 'pad', which says to use the terminal colors of the gradient to fill the remainder of the target region, 'reflect', which says to reflect the gradient pattern start-to-end, end-to-start, start-to-end, etc. continuously until the target rectangle is filled, and repeat, which says to repeat the gradient pattern start-to-end, start-to-end, start-to-end, etc. continuously until the target region is filled.
If the атрибут is not specified, the effect is as if a value of 'pad' were specified.
Animatable: yes.
xlink:href = "<iri>": An IRI reference to a different ‘linearGradient’ or ‘radialGradient’ елемент within the current SVG document fragment. Any ‘linearGradient’ атрибути which are defined on the referenced елемент which are not defined on this елемент are inherited by this елемент. If this елемент has no defined gradient stops, and the referenced елемент does (possibly due to its own ‘xlink:href’ атрибут), then this елемент inherits the gradient stop from the referenced елемент. Inheritance can be indirect to an arbitrary level; thus, if the referenced елемент inherits атрибут or gradient stops due to its own ‘xlink:href’ атрибут, then the current елемент can inherit those атрибути or gradient stops.
Animatable: yes.

Percentages are allowed for ‘x1’, ‘y1’, ‘x2’ and ‘y2’. For gradientUnits="userSpaceOnUse", percentages represent values relative to the current viewport. For gradientUnits="objectBoundingBox", percentages represent values relative to the bounding box for the object.

If ‘x1’ = ‘x2’ and ‘y1’ = ‘y2’, then the area to be painted will be painted as a single color using the color and opacity of the last gradient stop.

Properties inherit into the ‘linearGradient’ елемент from its ancestors; властивості do not inherit from the елемент referencing the ‘linearGradient’ елемент.

‘linearGradient’ елементи are never rendered directly; their only usage is as something that can be referenced using the ‘fill’ and ‘stroke’ властивості. The ‘display’ властивість does not apply to the ‘linearGradient’ елемент; thus, ‘linearGradient’ елементи are not directly rendered even if the ‘display’ властивість is set to a value other than none, and ‘linearGradient’ елементи are available for referencing even when the ‘display’ властивість on the ‘linearGradient’ елемент or any of its ancestors is set to none.

Example lingrad01 shows how to fill a rectangle by referencing a linear gradient paint server.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="8cm" height="4cm" viewBox="0 0 800 400" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>Example lingrad01 - fill a rectangle using a 
           linear gradient paint server</desc>
  <g>
    <defs>
      <linearGradient id="MyGradient">
        <stop offset="5%" stop-color="#F60" />
        <stop offset="95%" stop-color="#FF6" />
      </linearGradient>
    </defs>

    <!-- Outline the drawing area in blue -->
    <rect fill="none" stroke="blue" 
          x="1" y="1" width="798" height="398"/>

    <!-- The rectangle is filled using a linear gradient paint server -->
    <rect fill="url(#MyGradient)" stroke="black" stroke-width="5"  
          x="100" y="100" width="600" height="200"/>
  </g>
</svg>

Example lingrad01

View this example as SVG (SVG-enabled browsers only)

13.2.3 Radial gradients

Radial gradients are defined by a ‘radialGradient’ елемент.

‘radialGradient’

Categories:

Gradient елемент

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’
‘animate’
‘animateTransform’
‘set’
‘stop’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘cx’
‘cy’
‘r’
‘fx’
‘fy’
‘gradientUnits’
‘gradientTransform’
‘spreadMethod’
‘xlink:href’

DOM Інтерфейсs:

SVGRadialGradientElement

Attribute definitions:

gradientUnits = "userSpaceOnUse | objectBoundingBox": Defines the coordinate system for атрибути ‘cx’, ‘cy’, ‘r’, ‘fx’ and ‘fy’.
If gradientUnits="userSpaceOnUse", ‘cx’, ‘cy’, ‘r’, ‘fx’ and ‘fy’ represent values in the coordinate system that results from taking the current user coordinate system in place at the time when the gradient елемент is referenced (i.e., the user coordinate system for the елемент referencing the gradient елемент via a ‘fill’ or ‘stroke’ властивість) and then applying the transform specified by атрибут ‘gradientTransform’.
If gradientUnits="objectBoundingBox", the user coordinate system for атрибути ‘cx’, ‘cy’, ‘r’, ‘fx’ and ‘fy’ is established using the bounding box of the елемент to which the gradient is applied (see Object bounding box units) and then applying the transform specified by атрибут ‘gradientTransform’.
When gradientUnits="objectBoundingBox" and ‘gradientTransform’ is the identity matrix, then the rings of the radial gradient are circular with respect to the object bounding box space (i.e., the abstract coordinate system where (0,0) is at the top/left of the object bounding box and (1,1) is at the bottom/right of the object bounding box). When the object's bounding box is not square, the rings that are conceptually circular within object bounding box space will render as elliptical due to application of the non-uniform scaling transformation from bounding box space to user space.
If атрибут ‘gradientUnits’ is not specified, then the effect is as if a value of 'objectBoundingBox' were specified.
Animatable: yes.
gradientTransform = "<transform-list>": Contains the definitions of an optional additional transformation from the gradient coordinate system onto the target coordinate system (i.e., userSpaceOnUse or objectBoundingBox). This allows for things such as skewing the gradient. This additional transformation matrix is post-multiplied to (i.e., inserted to the right of) any previously defined transformations, including the implicit transformation necessary to convert from object bounding box units to user space.
If атрибут ‘gradientTransform’ is not specified, then the effect is as if an identity transform were specified.
Animatable: yes.
cx = "<coordinate>": ‘cx’, ‘cy’ and ‘r’ define the largest (i.e., outermost) circle for the radial gradient. The gradient will be drawn such that the 100% gradient stop is mapped to the perimeter of this largest (i.e., outermost) circle.
If the атрибут is not specified, the effect is as if a value of '50%' were specified.
Animatable: yes.
cy = "<coordinate>": See ‘cx’.
If the атрибут is not specified, the effect is as if a value of '50%' were specified.
Animatable: yes.
r = "<length>": See ‘cx’.
A negative value is an error (see Error processing). A value of zero will cause the area to be painted as a single color using the color and opacity of the last gradient stop.
If the атрибут is not specified, the effect is as if a value of '50%' were specified.
Animatable: yes.
fx = "<coordinate>": ‘fx’ and ‘fy’ define the focal point for the radial gradient. The gradient will be drawn such that the 0% gradient stop is mapped to (fx, fy).
If атрибут ‘fx’ is not specified, ‘fx’ will coincide with the presentational value of ‘cx’ for the елемент whether the value for 'cx' was inherited or not. If the елемент references an елемент that specifies a value for 'fx', then the value of 'fx' is inherited from the referenced елемент.
Animatable: yes.
fy = "<coordinate>": See ‘fx’.
If атрибут ‘fy’ is not specified, ‘fy’ will coincide with the presentational value of ‘cy’ for the елемент whether the value for 'cy' was inherited or not. If the елемент references an елемент that specifies a value for 'fy', then the value of 'fy' is inherited from the referenced елемент.
Animatable: yes.
spreadMethod = "pad | reflect | repeat": Indicates what happens if the gradient starts or ends inside the bounds of the object(s) being painted by the gradient. Has the same values and meanings as the ‘spreadMethod’ атрибут on ‘linearGradient’ елемент.
Animatable: yes.
xlink:href = "<iri>": An IRI reference to a different ‘linearGradient’ or ‘radialGradient’ елемент within the current SVG document fragment. Any ‘radialGradient’ атрибути which are defined on the referenced елемент which are not defined on this елемент are inherited by this елемент. If this елемент has no defined gradient stops, and the referenced елемент does (possibly due to its own ‘xlink:href’ атрибут), then this елемент inherits the gradient stop from the referenced елемент. Inheritance can be indirect to an arbitrary level; thus, if the referenced елемент inherits атрибут or gradient stops due to its own ‘xlink:href’ атрибут, then the current елемент can inherit those атрибути or gradient stops.
Animatable: yes.

Percentages are allowed for атрибути ‘cx’, ‘cy’, ‘r’, ‘fx’ and ‘fy’. For gradientUnits="userSpaceOnUse", percentages represent values relative to the current viewport. For gradientUnits="objectBoundingBox", percentages represent values relative to the bounding box for the object.

If the point defined by ‘fx’ and ‘fy’ lies outside the circle defined by ‘cx’, ‘cy’ and ‘r’, then the user agent shall set the focal point to the intersection of the line from (‘cx’, ‘cy’) to (‘fx’, ‘fy’) with the circle defined by ‘cx’, ‘cy’ and ‘r’.

Properties inherit into the ‘radialGradient’ елемент from its ancestors; властивості do not inherit from the елемент referencing the ‘radialGradient’ елемент.

‘radialGradient’ елементи are never rendered directly; their only usage is as something that can be referenced using the ‘fill’ and ‘stroke’ властивості. The ‘display’ властивість does not apply to the ‘radialGradient’ елемент; thus, ‘radialGradient’ елементи are not directly rendered even if the ‘display’ властивість is set to a value other than none, and ‘radialGradient’ елементи are available for referencing even when the ‘display’ властивість on the ‘radialGradient’ елемент or any of its ancestors is set to none.

Example radgrad01 shows how to fill a rectangle by referencing a radial gradient paint server.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="8cm" height="4cm" viewBox="0 0 800 400" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <desc>Example radgrad01 - fill a rectangle by referencing a 
           radial gradient paint server</desc>
  <g>
    <defs>
      <radialGradient id="MyGradient" gradientUnits="userSpaceOnUse"
                      cx="400" cy="200" r="300" fx="400" fy="200">
        <stop offset="0%" stop-color="red" />
        <stop offset="50%" stop-color="blue" />
        <stop offset="100%" stop-color="red" />
      </radialGradient>
    </defs>

    <!-- Outline the drawing area in blue -->
    <rect fill="none" stroke="blue" 
          x="1" y="1" width="798" height="398"/>

    <!-- The rectangle is filled using a radial gradient paint server -->
    <rect fill="url(#MyGradient)" stroke="black" stroke-width="5"  
          x="100" y="100" width="600" height="200"/>
  </g>
</svg>

Example radgrad01

View this example as SVG (SVG-enabled browsers only)

13.2.4 Gradient stops

The ramp of colors to use on a gradient is defined by the ‘stop’ елементи that are child елементи to either the ‘linearGradient’ елемент or the ‘radialGradient’ елемент.

‘stop’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘animateColor’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘offset’

DOM Інтерфейсs:

SVGStopElement

Attribute definitions:

offset = "<number> | <percentage>": The ‘offset’ атрибут is either a <number> (usually ranging from 0 to 1) or a <percentage> (usually ranging from 0% to 100%) which indicates where the gradient stop is placed. For linear gradients, the ‘offset’ атрибут represents a location along the gradient vector. For radial gradients, it represents a percentage distance from (fx,fy) to the edge of the outermost/largest circle.
Animatable: yes.

The ‘stop-color’ властивість indicates what color to use at that gradient stop. The keyword currentColor and ICC colors can be specified in the same manner as within a <paint> specification for the ‘fill’ and ‘stroke’ властивості.

‘stop-color’

Value:	currentColor \| <color> <icccolor> \| inherit
Initial:	black
Applies to:	‘stop’ елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

The ‘stop-opacity’ властивість defines the opacity of a given gradient stop.

‘stop-opacity’

Value:	<opacity-value> \| inherit
Initial:	1
Applies to:	‘stop’ елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

Some notes on gradients:

Gradient offset values less than 0 (or less than 0%) are rounded up to 0%. Gradient offset values greater than 1 (or greater than 100%) are rounded down to 100%.
It is necessary that at least two stops defined to have a gradient effect. If no stops are defined, then painting shall occur as if 'none' were specified as the paint style. If one stop is defined, then paint with the solid color fill using the color defined for that gradient stop.
Each gradient offset value is required to be equal to or greater than the previous gradient stop's offset value. If a given gradient stop's offset value is not equal to or greater than all previous offset values, then the offset value is adjusted to be equal to the largest of all previous offset values.
If two gradient stops have the same offset value, then the latter gradient stop controls the color value at the overlap point. In particular:
```
<stop offset="0" stop-color="white"/>
<stop offset=".2" stop-color="red"/>
<stop offset=".2" stop-color="blue"/>
<stop offset="1" stop-color="black"/>
```
will have approximately the same effect as:
```
<stop offset="0" stop-color="white"/>
<stop offset=".1999999999" stop-color="red"/>
<stop offset=".2" stop-color="blue"/>
<stop offset="1" stop-color="black"/>
```
which is a gradient that goes smoothly from white to red, then abruptly shifts from red to blue, and then goes smoothly from blue to black.

13.3 Patterns

A pattern is used to fill or stroke an object using a pre-defined graphic object which can be replicated ("tiled") at fixed intervals in x and y to cover the areas to be painted. Patterns are defined using a ‘pattern’ елемент and then referenced by властивості ‘fill’ and ‘stroke’ on a given graphics елемент to indicate that the given елемент shall be filled or stroked with the referenced pattern.

Attributes ‘x’, ‘y’, ‘width’, ‘height’ and ‘patternUnits’ define a reference rectangle somewhere on the infinite canvas. The reference rectangle has its top/left at (x, y) and its bottom/right at (x + width, y + height). The tiling theoretically extends a series of such rectangles to infinity in X and Y (positive and negative), with rectangles starting at (x + m*width, y + n* height) for each possible integer value for m and n.

‘pattern’

Categories:

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘viewBox’
‘preserveAspectRatio’
‘x’
‘y’
‘width’
‘height’
‘patternUnits’
‘patternContentUnits’
‘patternTransform’
‘xlink:href’

DOM Інтерфейсs:

SVGPatternElement

Attribute definitions:

patternUnits = "userSpaceOnUse | objectBoundingBox"

Defines the coordinate system for атрибути ‘x’, ‘y’, ‘width’ and ‘height’.
If patternUnits="userSpaceOnUse", ‘x’, ‘y’, ‘width’ and ‘height’ represent values in the coordinate system that results from taking the current user coordinate system in place at the time when the ‘pattern’ елемент is referenced (i.e., the user coordinate system for the елемент referencing the ‘pattern’ елемент via a ‘fill’ or ‘stroke’ властивість) and then applying the transform specified by атрибут ‘patternTransform’.
If patternUnits="objectBoundingBox", the user coordinate system for атрибути ‘x’, ‘y’, ‘width’ and ‘height’ is established using the bounding box of the елемент to which the pattern is applied (see Object bounding box units) and then applying the transform specified by атрибут ‘patternTransform’.
If атрибут ‘patternUnits’ is not specified, then the effect is as if a value of 'objectBoundingBox' were specified.
Animatable: yes.

patternContentUnits = "userSpaceOnUse | objectBoundingBox"

Defines the coordinate system for the contents of the ‘pattern’. Note that this атрибут has no effect if атрибут ‘viewBox’ is specified.
If patternContentUnits="userSpaceOnUse", the user coordinate system for the contents of the ‘pattern’ елемент is the coordinate system that results from taking the current user coordinate system in place at the time when the ‘pattern’ елемент is referenced (i.e., the user coordinate system for the елемент referencing the ‘pattern’ елемент via a ‘fill’ or ‘stroke’ властивість) and then applying the transform specified by атрибут ‘patternTransform’.
If patternContentUnits="objectBoundingBox", the user coordinate system for the contents of the ‘pattern’ елемент is established using the bounding box of the елемент to which the pattern is applied (see Object bounding box units) and then applying the transform specified by атрибут ‘patternTransform’.
If атрибут ‘patternContentUnits’ is not specified, then the effect is as if a value of 'userSpaceOnUse' were specified.
Animatable: yes.

patternTransform = "<transform-list>"

Contains the definition of an optional additional transformation from the pattern coordinate system onto the target coordinate system (i.e., 'userSpaceOnUse' or 'objectBoundingBox'). This allows for things such as skewing the pattern tiles. This additional transformation matrix is post-multiplied to (i.e., inserted to the right of) any previously defined transformations, including the implicit transformation necessary to convert from object bounding box units to user space.
If атрибут ‘patternTransform’ is not specified, then the effect is as if an identity transform were specified.
Animatable: yes.

x = "<coordinate>"

‘x’, ‘y’, ‘width’ and ‘height’ indicate how the pattern tiles are placed and spaced. These атрибути represent coordinates and values in the coordinate space specified by the combination of атрибути ‘patternUnits’ and ‘patternTransform’.
If the атрибут is not specified, the effect is as if a value of zero were specified.
Animatable: yes.

y = "<coordinate>"

See ‘x’.
If the атрибут is not specified, the effect is as if a value of zero were specified.
Animatable: yes.

width = "<length>"

See ‘x’.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент (i.e., no paint is applied).
If the атрибут is not specified, the effect is as if a value of zero were specified.
Animatable: yes.

height = "<length>"

xlink:href = "<iri>"

An IRI reference to a different ‘pattern’ елемент within the current SVG document fragment. Any атрибути which are defined on the referenced елемент which are not defined on this елемент are inherited by this елемент. If this елемент has no children, and the referenced елемент does (possibly due to its own ‘xlink:href’ атрибут), then this елемент inherits the children from the referenced елемент. Inheritance can be indirect to an arbitrary level; thus, if the referenced елемент inherits атрибути or children due to its own ‘xlink:href’ атрибут, then the current елемент can inherit those атрибути or children.
Animatable: yes.

preserveAspectRatio = "[defer] <align> [<meetOrSlice>]"

View this example as SVG (SVG-enabled browsers only)

If the атрибут is not specified, then the effect is as if a value of xMidYMid meet were specified.

Animatable: yes.

SVG's user agent style sheet sets the ‘overflow’ властивість for ‘pattern’ елементи to hidden, which causes a rectangular clipping path to be created at the bounds of the pattern tile. Unless the ‘overflow’ властивість is overridden, any graphics within the pattern which goes outside of the pattern rectangle will be clipped. Note that if the ‘overflow’ властивість is set to visible the rendering behavior for the pattern is undefined. Example pattern01 below shows the effect of clipping to the pattern tile.

The contents of the ‘pattern’ are relative to a new coordinate system. If there is a ‘viewBox’ атрибут, then the new coordinate system is fitted into the region defined by the ‘x’, ‘y’, ‘width’, ‘height’ and ‘patternUnits’ атрибути on the ‘pattern’ елемент using the standard rules for ‘viewBox’ and ‘preserveAspectRatio’. If there is no ‘viewBox’ атрибут, then the new coordinate system has its origin at (x, y), where x is established by the ‘x’ атрибут on the ‘pattern’ елемент, and y is established by the ‘y’ атрибут on the ‘pattern’ елемент. Thus, in the following example:

<pattern x="10" y="10" width="20" height="20">
   <rect x="5" y="5" width="10" height="10"/>
</pattern>

the rectangle has its top/left located 5 units to the right and 5 units down from the origin of the pattern tile.

The ‘viewBox’ атрибут introduces a supplemental transformation which is applied on top of any transformations necessary to create a new pattern coordinate system due to атрибути ‘x’, ‘y’, ‘width’, ‘height’ and ‘patternUnits’.

Properties inherit into the ‘pattern’ елемент from its ancestors; властивості do not inherit from the елемент referencing the ‘pattern’ елемент.

‘pattern’ елементи are never rendered directly; their only usage is as something that can be referenced using the ‘fill’ and ‘stroke’ властивості. The ‘display’ властивість does not apply to the ‘pattern’ елемент; thus, ‘pattern’ елементи are not directly rendered even if the ‘display’ властивість is set to a value other than none, and ‘pattern’ елементи are available for referencing even when the ‘display’ властивість on the ‘pattern’ елемент or any of its ancestors is set to none.

Event атрибути and event listeners attached to the contents of a ‘pattern’ елемент are not processed; only the rendering aspects of ‘pattern’ елементи are processed.

Example pattern01 shows how to fill a rectangle by referencing a pattern paint server. Note how the blue stroke of each triangle has been clipped at the top and the left. This is due to SVG's user agent style sheet setting the ‘overflow’ властивість for ‘pattern’ елементи to hidden, which causes the pattern to be clipped to the bounds of the pattern tile.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="8cm" height="4cm" viewBox="0 0 800 400" version="1.1"
     xmlns="http://www.w3.org/2000/svg">
  <defs>
    <pattern id="TrianglePattern" patternUnits="userSpaceOnUse"
             x="0" y="0" width="100" height="100"
             viewBox="0 0 10 10" >
      <path d="M 0 0 L 7 0 L 3.5 7 z" fill="red" stroke="blue" />
    </pattern> 
  </defs>

  <!-- Outline the drawing area in blue -->
  <rect fill="none" stroke="blue" 
        x="1" y="1" width="798" height="398"/>

  <!-- The ellipse is filled using a triangle pattern paint server
       and stroked with black -->
  <ellipse fill="url(#TrianglePattern)" stroke="black" stroke-width="5"  
           cx="400" cy="200" rx="350" ry="150" />
</svg>

Example pattern01

13.4 DOM interfaces

13.4.1 Інтерфейс SVGGradientElement

The SVGGradientElement interface is a base interface used by SVGLinearGradientElement and SVGRadialGradientElement.

interface SVGGradientElement : SVGElement,
                               SVGURIReference,
                               SVGExternalResourcesRequired,
                               SVGStylable,
                               SVGUnitTypes {

  // Spread Method Types
  const unsigned short SVG_SPREADMETHOD_UNKNOWN = 0;
  const unsigned short SVG_SPREADMETHOD_PAD = 1;
  const unsigned short SVG_SPREADMETHOD_REFLECT = 2;
  const unsigned short SVG_SPREADMETHOD_REPEAT = 3;

  readonly атрибут SVGAnimatedEnumeration gradientUnits;
  readonly атрибут SVGAnimatedTransformList gradientTransform;
  readonly атрибут SVGAnimatedEnumeration spreadMethod;
};

Constants in group “Spread Method Types”:

SVG_SPREADMETHOD_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_SPREADMETHOD_PAD (unsigned short): Corresponds to value 'pad'.
SVG_SPREADMETHOD_REFLECT (unsigned short): Corresponds to value 'reflect'.
SVG_SPREADMETHOD_REPEAT (unsigned short): Corresponds to value 'repeat'.

Attributes:

gradientUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘gradientUnits’ on the given елемент. Takes one of the constants defined in SVGUnitTypes.
gradientTransform (readonly SVGAnimatedTransformList): Corresponds to атрибут ‘gradientTransform’ on the given елемент.
spreadMethod (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘spreadMethod’ on the given елемент. One of the Spread Method Types defined on this interface.

13.4.2 Інтерфейс SVGLinearGradientElement

The SVGLinearGradientElement interface corresponds to the ‘linearGradient’ елемент.

interface SVGLinearGradientElement : SVGGradientElement {
  readonly атрибут SVGAnimatedLength x1;
  readonly атрибут SVGAnimatedLength y1;
  readonly атрибут SVGAnimatedLength x2;
  readonly атрибут SVGAnimatedLength y2;
};

Attributes:

x1 (readonly SVGAnimatedLength): Corresponds to атрибут ‘x1’ on the given ‘linearGradient’ елемент.
y1 (readonly SVGAnimatedLength): Corresponds to атрибут ‘y1’ on the given ‘linearGradient’ елемент.
x2 (readonly SVGAnimatedLength): Corresponds to атрибут ‘x2’ on the given ‘linearGradient’ елемент.
y2 (readonly SVGAnimatedLength): Corresponds to атрибут ‘y2’ on the given ‘linearGradient’ елемент.

13.4.3 Інтерфейс SVGRadialGradientElement

The SVGRadialGradientElement interface corresponds to the ‘radialGradient’ елемент.

interface SVGRadialGradientElement : SVGGradientElement {
  readonly атрибут SVGAnimatedLength cx;
  readonly атрибут SVGAnimatedLength cy;
  readonly атрибут SVGAnimatedLength r;
  readonly атрибут SVGAnimatedLength fx;
  readonly атрибут SVGAnimatedLength fy;
};

Attributes:

cx (readonly SVGAnimatedLength): Corresponds to атрибут ‘cx’ on the given ‘radialGradient’ елемент.
cy (readonly SVGAnimatedLength): Corresponds to атрибут ‘cy’ on the given ‘radialGradient’ елемент.
r (readonly SVGAnimatedLength): Corresponds to атрибут ‘r’ on the given ‘radialGradient’ елемент.
fx (readonly SVGAnimatedLength): Corresponds to атрибут ‘fx’ on the given ‘radialGradient’ елемент.
fy (readonly SVGAnimatedLength): Corresponds to атрибут ‘fy’ on the given ‘radialGradient’ елемент.

13.4.4 Інтерфейс SVGStopElement

The SVGStopElement interface corresponds to the ‘stop’ елемент.

interface SVGStopElement : SVGElement,
                           SVGStylable {
  readonly атрибут SVGAnimatedNumber offset;
};

Attributes:

offset (readonly SVGAnimatedNumber): Corresponds to атрибут ‘offset’ on the given ‘stop’ елемент.

13.4.5 Інтерфейс SVGPatternElement

The SVGPatternElement interface corresponds to the ‘pattern’ елемент.

interface SVGPatternElement : SVGElement,
                              SVGURIReference,
                              SVGTests,
                              SVGLangSpace,
                              SVGExternalResourcesRequired,
                              SVGStylable,
                              SVGFitToViewBox,
                              SVGUnitTypes {
  readonly атрибут SVGAnimatedEnumeration patternUnits;
  readonly атрибут SVGAnimatedEnumeration patternContentUnits;
  readonly атрибут SVGAnimatedTransformList patternTransform;
  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
  readonly атрибут SVGAnimatedLength width;
  readonly атрибут SVGAnimatedLength height;
};

Attributes:

patternUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘patternUnits’ on the given ‘pattern’ елемент. Takes one of the constants defined in SVGUnitTypes.
patternContentUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘patternContentUnits’ on the given ‘pattern’ елемент. Takes one of the constants defined in SVGUnitTypes.
patternTransform (readonly SVGAnimatedTransformList): Corresponds to атрибут ‘patternTransform’ on the given ‘pattern’ елемент.
x (readonly SVGAnimatedLength): Corresponds to атрибут ‘x’ on the given ‘pattern’ елемент.
y (readonly SVGAnimatedLength): Corresponds to атрибут ‘y’ on the given ‘pattern’ елемент.
width (readonly SVGAnimatedLength): Corresponds to атрибут ‘width’ on the given ‘pattern’ елемент.
height (readonly SVGAnimatedLength): Corresponds to атрибут ‘height’ on the given ‘pattern’ елемент.

14 Clipping, Masking and Compositing

14.1 Вступ
14.2 Simple alpha compositing
14.3 Clipping paths
14.4 Masking
14.5 Object and group opacity: the ‘opacity’ властивість
14.6 DOM interfaces
- 14.6.1 Інтерфейс SVGClipPathElement
- 14.6.2 Інтерфейс SVGMaskElement

14.1 Вступ

SVG supports the following clipping/masking features:

clipping paths, which uses any combination of ‘path’, ‘text’ and basic shapes to serve as the outline of a (in the absence of anti-aliasing) 1-bit mask, where everything on the "inside" of the outline is allowed to show through but everything on the outside is masked out
masks, which are container елементи which can contain graphics елементи or other container елементи which define a set of graphics that is to be used as a semi-transparent mask for compositing foreground objects into the current background.

One key distinction between a clipping path and a mask is that clipping paths are hard masks (i.e., the silhouette consists of either fully opaque pixels or fully transparent pixels, with the possible exception of anti-aliasing along the edge of the silhouette) whereas masks consist of an image where each pixel value indicates the degree of transparency vs. opacity. In a mask, each pixel value can range from fully transparent to fully opaque.

SVG supports only simple alpha blending compositing (see Simple Alpha Compositing).

14.2 Simple alpha compositing

Graphics елементи are blended into the елементи already rendered on the canvas using simple alpha compositing, in which the resulting color and opacity at any given pixel on the canvas is the result of the following formulas (all color values use premultiplied alpha):

Er, Eg, Eb    - Element color value
Ea            - Element alpha value
Cr, Cg, Cb    - Canvas color value (before blending)
Ca            - Canvas alpha value (before blending)
Cr', Cg', Cb' - Canvas color value (after blending)
Ca'           - Canvas alpha value (after blending)
Ca' = 1 - (1 - Ea) * (1 - Ca)
Cr' = (1 - Ea) * Cr + Er
Cg' = (1 - Ea) * Cg + Eg
Cb' = (1 - Ea) * Cb + Eb

The following rendering властивості, which provide information about the color space in which to perform the compositing operations, apply to compositing operations:

‘color-interpolation’
‘color-rendering’

14.3 Clipping paths

14.3.1 Вступ

The clipping path restricts the region to which paint can be applied. Conceptually, any parts of the drawing that lie outside of the region bounded by the currently active clipping path are not drawn. A clipping path can be thought of as a mask wherein those pixels outside the clipping path are black with an alpha value of zero and those pixels inside the clipping path are white with an alpha value of one (with the possible exception of anti-aliasing along the edge of the silhouette).

14.3.2 The initial clipping path

When an ‘svg’ елемент is either the root елемент in the document or is embedded within a document whose layout is determined according to the layout rules of CSS or XSL, then the user agent must establish an initial clipping path for the SVG document fragment. The ‘overflow’ and ‘clip’ властивості along with additional SVG user agent processing rules determine the initial clipping path which the user agent establishes for the SVG document fragment:

14.3.3 The ‘overflow’ and ‘clip’ властивості

‘overflow’

Value:	visible \| hidden \| scroll \| auto \| inherit
Initial:	see prose
Applies to:	елементи which establish a new viewport, ‘pattern’ елементи and ‘marker’ елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

The ‘overflow’ властивість has the same parameter values and has the same meaning as defined in CSS2 ([CSS2], section 11.1.1); however, the following additional points apply:

The ‘overflow’ властивість applies to елементи that establish new viewports (e.g., ‘svg’ елементи), ‘pattern’ елементи and ‘marker’ елементи. For all other елементи, the властивість has no effect (i.e., a clipping rectangle is not created).
For those елементи to which the ‘overflow’ властивість can apply, if the ‘overflow’ властивість has the value hidden or scroll, the effect is that a new clipping path in the shape of a rectangle is created. The result is equivalent to defining a ‘clipPath’ елемент whose content is a ‘rect’ елемент which defines the equivalent rectangle, and then specifying the <uri> of this ‘clipPath’ елемент on the ‘clip-path’ властивість for the given елемент.
If the ‘overflow’ властивість has a value other than hidden or scroll, the властивість has no effect (i.e., a clipping rectangle is not created).
Within SVG content, the value auto is equivalent to the value visible.
When an outermost svg елемент is embedded inline within a parent XML grammar which uses CSS layout ([CSS2], chapter 9) or XSL formatting [XSL], if the ‘overflow’ властивість has the value hidden or scroll, then the user agent will establish an initial clipping path equal to the bounds of the initial viewport; otherwise, the initial clipping path is set according to the clipping rules as defined in CSS2 ([CSS2], section 11.1.1).
When an outermost svg елемент is stand-alone or embedded inline within a parent XML grammar which does not use CSS layout or XSL formatting, the ‘overflow’ властивість on the outermost svg елемент is ignored for the purposes of visual rendering and the initial clipping path is set to the bounds of the initial viewport.
The initial value for ‘overflow’ as defined in [CSS2-overflow] is 'visible', and this applies also to the root ‘svg’ елемент; however, for child елементи of an SVG document, SVG's user agent style sheet overrides this initial value and sets the ‘overflow’ властивість on елементи that establish new viewports (e.g., ‘svg’ елементи), ‘pattern’ елементи and ‘marker’ елементи to the value 'hidden'.

As a result of the above, the default behavior of SVG user agents is to establish a clipping path to the bounds of the initial viewport and to establish a new clipping path for each елемент which establishes a new viewport and each ‘pattern’ and ‘marker’ елемент.

For related information, see Clip to viewport vs. clip to ‘viewBox’.

‘clip’

Value:	<shape> \| auto \| inherit
Initial:	auto
Applies to:	елементи which establish a new viewport, ‘pattern’ елементи and ‘marker’ елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

The ‘clip’ властивість has the same parameter values as defined in CSS2 ([CSS2], section 11.1.2). Unitless values, which indicate current user coordinates, are permitted on the coordinate values on the <shape>. The value of auto defines a clipping path along the bounds of the viewport created by the given елемент.

14.3.4 Clip to viewport vs. clip to ‘viewBox’

It is important to note that initial values for the ‘overflow’ and ‘clip’ властивості and the user agent style sheet will result in an initial clipping path that is set to the bounds of the initial viewport. When атрибути ‘viewBox’ and ‘preserveAspectRatio’ атрибути are specified, it is sometime desirable that the clipping path be set to the bounds of the ‘viewBox’ instead of the viewport (or reference rectangle, in the case of ‘marker’ and ‘pattern’ елементи), particularly when ‘preserveAspectRatio’ specifies uniform scaling and the aspect ratio of the ‘viewBox’ does not match the aspect ratio of the viewport.

To set the initial clipping path to the bounds of the ‘viewBox’, set the bounds of ‘clip’ властивість to the same rectangle as specified on the ‘viewBox’ атрибут. (Note that the parameters do not match. ‘clip’ takes values <top>, <right>,<bottom> and <left>, whereas ‘viewBox’ takes values <min-x>, <min-y>, <width> and <height>.)

14.3.5 Establishing a new clipping path: the ‘clipPath’ елемент

A clipping path is defined with a ‘clipPath’ елемент. A clipping path is used/referenced using the ‘clip-path’ властивість.

A ‘clipPath’ елемент can contain ‘path’ елементи, ‘text’ елементи, basic shapes (such as ‘circle’) or a ‘use’ елемент. If a ‘use’ елемент is a child of a ‘clipPath’ елемент, it must directly reference ‘path’, ‘text’ or basic shape елементи. Indirect references are an error (see Error processing).

The raw geometry of each child елемент exclusive of rendering властивості such as ‘fill’, ‘stroke’, ‘stroke-width’ within a ‘clipPath’ conceptually defines a 1-bit mask (with the possible exception of anti-aliasing along the edge of the geometry) which represents the silhouette of the graphics associated with that елемент. Anything outside the outline of the object is masked out. If a child елемент is made invisible by ‘display’ or ‘visibility’ it does not contribute to the clipping path. When the ‘clipPath’ елемент contains multiple child елементи, the silhouettes of the child елементи are logically OR'd together to create a single silhouette which is then used to restrict the region onto which paint can be applied. Thus, a point is inside the clipping path if it is inside any of the children of the ‘clipPath’.

For a given graphics елемент, the actual clipping path used will be the intersection of the clipping path specified by its ‘clip-path’ властивість (if any) with any clipping paths on its ancestors, as specified by the ‘clip-path’ властивість on the ancestor елементи, or by the ‘overflow’ властивість on ancestor елементи which establish a new viewport. Also, see the discussion of the initial clipping path.)

A couple of notes:

The ‘clipPath’ елемент itself and its child елементи do not inherit clipping paths from the ancestors of the ‘clipPath’ елемент.
The ‘clipPath’ елемент or any of its children can specify властивість ‘clip-path’.
If a valid ‘clip-path’ reference is placed on a ‘clipPath’ елемент, the resulting clipping path is the intersection of the contents of the ‘clipPath’ елемент with the referenced clipping path.
If a valid ‘clip-path’ reference is placed on one of the children of a ‘clipPath’ елемент, then the given child елемент is clipped by the referenced clipping path before OR'ing the silhouette of the child елемент with the silhouettes of the other child елементи.
An empty clipping path will completely clip away the елемент that had the ‘clip-path’ властивість applied.

‘clipPath’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘clipPathUnits’

DOM Інтерфейсs:

SVGClipPathElement

Attribute definitions:

clipPathUnits = "userSpaceOnUse | objectBoundingBox": Defines the coordinate system for the contents of the ‘clipPath’.
If clipPathUnits="userSpaceOnUse", the contents of the ‘clipPath’ represent values in the current user coordinate system in place at the time when the ‘clipPath’ елемент is referenced (i.e., the user coordinate system for the елемент referencing the ‘clipPath’ елемент via the ‘clip-path’ властивість).
If clipPathUnits="objectBoundingBox", then the user coordinate system for the contents of the ‘clipPath’ елемент is established using the bounding box of the елемент to which the clipping path is applied (see Object bounding box units).
If атрибут ‘clipPathUnits’ is not specified, then the effect is as if a value of 'userSpaceOnUse' were specified.
Animatable: yes.

Properties inherit into the ‘clipPath’ елемент from its ancestors; властивості do not inherit from the елемент referencing the ‘clipPath’ елемент.

‘clipPath’ елементи are never rendered directly; their only usage is as something that can be referenced using the ‘clip-path’ властивість. The ‘display’ властивість does not apply to the ‘clipPath’ елемент; thus, ‘clipPath’ елементи are not directly rendered even if the ‘display’ властивість is set to a value other than none, and ‘clipPath’ елементи are available for referencing even when the ‘display’ властивість on the ‘clipPath’ елемент or any of its ancestors is set to none.

‘clip-path’

Value:	<funciri> \| none \| inherit
Initial:	none
Applies to:	container елементи, graphics елементи and ‘clipPath’
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

<funciri>: An IRI reference to another graphical object within the same SVG document fragment which will be used as the clipping path. If the IRI reference is not valid (e.g it points to an object that doesn't exist or the object is not a ‘clipPath’ елемент) the ‘clip-path’ властивість must be treated as if it hadn't been specified.

‘clip-rule’

Value:	nonzero \| evenodd \| inherit
Initial:	nonzero
Applies to:	graphics елементи within a ‘clipPath’ елемент
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

nonzero: See description of ‘fill-rule’ властивість.
evenodd: See description of ‘fill-rule’ властивість.

The ‘clip-rule’ властивість only applies to graphics елементи that are contained within a ‘clipPath’ елемент. The following fragment of code will cause an evenodd clipping rule to be applied to the clipping path because ‘clip-rule’ is specified on the ‘path’ елемент that defines the clipping shape:

<g clip-rule="nonzero">
  <clipPath id="MyClip">
    <path d="..." clip-rule="evenodd" />
  </clipPath>
  <rect clip-path="url(#MyClip)" ... />
</g>

whereas the following fragment of code will not cause an evenodd clipping rule to be applied because the ‘clip-rule’ is specified on the referencing елемент, not on the object defining the clipping shape:

<g clip-rule="nonzero">
  <clipPath id="MyClip">
    <path d="..." />
  </clipPath>
  <rect clip-path="url(#MyClip)" clip-rule="evenodd" ... />
</g>

14.3.6 Clipping paths, geometry, and pointer events

A clipping path is conceptually equivalent to a custom viewport for the referencing елемент. Thus, it affects the rendering of an елемент, but not the елемент's inherent geometry. The bounding box of a clipped елемент (that is, an елемент which references a ‘clipPath’ елемент via a ‘clip-path’ властивість, or a child of the referencing елемент) must remain the same as if it were not clipped.

By default, pointer-events must not be dispatched on the clipped (non-visible) regions of a shape. For example, a circle with a radius of 10 which is clipped to a circle with a radius of 5 will not receive 'click' events outside the smaller radius. Later versions of SVG may define new властивості to enable fine-grained control over the interactions between hit testing and clipping.

14.4 Masking

In SVG, you can specify that any other graphics object or ‘g’ елемент can be used as an alpha mask for compositing the current object into the background.

A mask is defined with a ‘mask’ елемент. A mask is used/referenced using the ‘mask’ властивість.

A ‘mask’ can contain any graphical елементи or container елементи such as a ‘g’.

It is an error if the ‘mask’ властивість references a non-existent object or if the referenced object is not a ‘mask’ елемент (see Error Processing).

The effect is as if the child елементи of the ‘mask’ are rendered into an offscreen image which has been initialized to transparent black. Any graphical object which uses/references the given ‘mask’ елемент will be painted onto the background through the mask, thus completely or partially masking out parts of the graphical object.

For any graphics object that is used as a mask, the mask value at any point is computed from the color channel values and alpha channel value as follows. First a luminance value is computed from the color channel values:

If the computed value of ‘color-interpolation’ on the ‘mask’ елемент is linearRGB, first convert the original image color values (potentially in the sRGB color space) to the linear RGB color space (see Rendering властивості). Then, using non-premultiplied linear RGB color values, apply the luminance-to-alpha coefficients (as defined in the ‘feColorMatrix’ filter primitive) to convert the linear RGB color values to linear luminance values.
If the computed value of ‘color-interpolation’ on the ‘mask’ елемент is sRGB then the luminance value is calculated by taking the non-premultiplied RGB color values, applying the luminance-to-alpha coefficients (as defined in the ‘feColorMatrix’ filter primitive) to convert the RGB color values to luminance values.

Finally if the graphics object also includes an alpha channel, then the computed luminance value is multiplied by the corresponding alpha value to produce the mask value.

For a four-channel RGBA graphics object that is used as a mask, both the color channels and the alpha channel of the mask contribute to the masking operation. The alpha mask that is used to composite the current object into the background represents the product of the luminance of the color channels (see previous paragraph) and the alpha channel from the mask.

For a three-channel RGB graphics object that is used as a mask (e.g., when referencing a 3-channel image file), the effect is as if the object were converted into a 4-channel RGBA image with the alpha channel uniformly set to 1.

For a single-channel image that is used as a mask (e.g., when referencing a 1-channel grayscale image file), the effect is as if the object were converted into a 4-channel RGBA image, where the single channel from the referenced object is used to compute the three color channels and the alpha channel is uniformly set to 1. Note that when referencing a grayscale image file, the transfer curve relating the encoded grayscale values to linear light values must be taken into account when computing the color channels.

The effect of a mask is identical to what would have happened if there were no mask but instead the alpha channel of the given object were multiplied with the mask's resulting alpha values (i.e., the product of the mask's luminance from its color channels multiplied by the mask's alpha channel).

Note that SVG ‘path’s, shapes (e.g., ‘circle’) and ‘text’ are all treated as four-channel RGBA images for the purposes of masking operations.

Example mask01 uses an image to mask a rectangle.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="8cm" height="3cm" viewBox="0 0 800 300" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <desc>Example mask01 - blue text masked with gradient against red background
  </desc>
  <defs>
    <linearGradient id="Gradient" gradientUnits="userSpaceOnUse"
                    x1="0" y1="0" x2="800" y2="0">
      <stop offset="0" stop-color="white" stop-opacity="0" />
      <stop offset="1" stop-color="white" stop-opacity="1" />
    </linearGradient>
    <mask id="Mask" maskUnits="userSpaceOnUse"
          x="0" y="0" width="800" height="300">
      <rect x="0" y="0" width="800" height="300" fill="url(#Gradient)"  />
    </mask>
    <text id="Text" x="400" y="200" 
          font-family="Verdana" font-size="100" text-anchor="middle" >
      Masked text
    </text>
  </defs>

  <!-- Draw a pale red rectangle in the background -->
  <rect x="0" y="0" width="800" height="300" fill="#FF8080" />
  
  <!-- Draw the text string twice. First, filled blue, with the mask applied.
       Second, outlined in black without the mask. -->
  <use xlink:href="#Text" fill="blue" mask="url(#Mask)" />
  <use xlink:href="#Text" fill="none" stroke="black" stroke-width="2" />
</svg>

Example mask01

View this example as SVG (SVG-enabled browsers only)

‘mask’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘x’
‘y’
‘width’
‘height’
‘maskUnits’
‘maskContentUnits’

DOM Інтерфейсs:

SVGMaskElement

Attribute definitions:

maskUnits = "userSpaceOnUse | objectBoundingBox": Defines the coordinate system for атрибути ‘x’, ‘y’, ‘width’ and ‘height’.
If maskUnits="userSpaceOnUse", ‘x’, ‘y’, ‘width’ and ‘height’ represent values in the current user coordinate system in place at the time when the ‘mask’ елемент is referenced (i.e., the user coordinate system for the елемент referencing the ‘mask’ елемент via the ‘mask’ властивість).
If maskUnits="objectBoundingBox", ‘x’, ‘y’, ‘width’ and ‘height’ represent fractions or percentages of the bounding box of the елемент to which the mask is applied. (See Object bounding box units.)
If атрибут ‘maskUnits’ is not specified, then the effect is as if a value of 'objectBoundingBox' were specified.
Animatable: yes.
maskContentUnits = "userSpaceOnUse | objectBoundingBox": Defines the coordinate system for the contents of the ‘mask’.
If maskContentUnits="userSpaceOnUse", the user coordinate system for the contents of the ‘mask’ елемент is the current user coordinate system in place at the time when the ‘mask’ елемент is referenced (i.e., the user coordinate system for the елемент referencing the ‘mask’ елемент via the ‘mask’ властивість).
If maskContentUnits="objectBoundingBox", the user coordinate system for the contents of the ‘mask’ is established using the bounding box of the елемент to which the mask is applied. (See Object bounding box units.)
If атрибут ‘maskContentUnits’ is not specified, then the effect is as if a value of 'userSpaceOnUse' were specified.
Animatable: yes.
x = "<coordinate>": The x-axis coordinate of one corner of the rectangle for the largest possible offscreen buffer. Note that the clipping path used to render any graphics within the mask will consist of the intersection of the current clipping path associated with the given object and the rectangle defined by ‘x’, ‘y’, ‘width’ and ‘height’.
If the атрибут is not specified, the effect is as if a value of '-10%' were specified.
Animatable: yes.
y = "<coordinate>": The y-axis coordinate of one corner of the rectangle for the largest possible offscreen buffer.
If the атрибут is not specified, the effect is as if a value of '-10%' were specified.
Animatable: yes.
width = "<length>": The width of the largest possible offscreen buffer. Note that the clipping path used to render any graphics within the mask will consist of the intersection of the current clipping path associated with the given object and the rectangle defined by ‘x’, ‘y’, ‘width’ and ‘height’.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
If the атрибут is not specified, the effect is as if a value of '120%' were specified.
Animatable: yes.
height = "<length>": The height of the largest possible offscreen buffer.
A negative value is an error (see Error processing). A value of zero disables rendering of the елемент.
If the атрибут is not specified, the effect is as if a value of '120%' were specified.
Animatable: yes.

Properties inherit into the ‘mask’ елемент from its ancestors; властивості do not inherit from the елемент referencing the ‘mask’ елемент.

‘mask’ елементи are never rendered directly; their only usage is as something that can be referenced using the ‘mask’ властивість. The ‘opacity’, ‘filter’ and ‘display’ властивості do not apply to the ‘mask’ елемент; thus, ‘mask’ елементи are not directly rendered even if the ‘display’ властивість is set to a value other than none, and ‘mask’ елементи are available for referencing even when the ‘display’ властивість on the ‘mask’ елемент or any of its ancestors is set to none.

The following is a description of the ‘mask’ властивість.

‘mask’

Value:	<funciri> \| none \| inherit
Initial:	none
Applies to:	container елементи and graphics елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

<funciri>: A IRI reference to another graphical object which will be used as the mask.

14.5 Object and group opacity: the ‘opacity’ властивість

There are several opacity властивості within SVG:

‘fill-opacity’, which specifies the opacity of a fill operation;
‘stroke-opacity’, which specifies the opacity of a stroking operation;
‘stop-opacity’, which specifies the opacity of a gradient stop; and
‘opacity’, which specifies object/group opacity and which is described in this section.

Except for object/group opacity (described just below), all other opacity властивості are involved in intermediate rendering operations. Object/group opacity can be thought of conceptually as a postprocessing operation. Conceptually, after the object/group is rendered into an RGBA offscreen image, the object/group opacity setting specifies how to blend the offscreen image into the current background.

‘opacity’

Value:	<opacity-value> \| inherit
Initial:	1
Applies to:	container елементи (except ‘mask’) and graphics елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

<opacity-value>: The uniform opacity setting to be applied across an entire object, as a <number>. Any values outside the range 0.0 (fully transparent) to 1.0 (fully opaque) will be clamped to this range. (See Clamping values which are restricted to a particular range.) If the object is a container елемент such as a ‘g’, then the effect is as if the contents of the ‘g’ were blended against the current background using a mask where the value of each pixel of the mask is <opacity-value>. (See Simple alpha compositing.)

Example opacity01 illustrates various usage of the ‘opacity’ властивість on елементи and групи.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="12cm" height="3.5cm" viewBox="0 0 1200 350"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example opacity01 - opacity властивість</desc>

  <rect x="1" y="1" width="1198" height="348"
        fill="none" stroke="blue" />

  <!-- Background blue rectangle -->
  <rect x="100" y="100" width="1000" height="150" fill="#0000ff"  />

  <!-- Red circles going from opaque to nearly transparent -->
  <circle cx="200" cy="100" r="50" fill="red" opacity="1"  />
  <circle cx="400" cy="100" r="50" fill="red" opacity=".8"  />
  <circle cx="600" cy="100" r="50" fill="red" opacity=".6"  />
  <circle cx="800" cy="100" r="50" fill="red" opacity=".4"  />
  <circle cx="1000" cy="100" r="50" fill="red" opacity=".2"  />

  <!-- Opaque group, opaque circles -->
  <g opacity="1" >
    <circle cx="182.5" cy="250" r="50" fill="red" opacity="1"  />
    <circle cx="217.5" cy="250" r="50" fill="green" opacity="1"  />
  </g>
  <!-- Group opacity: .5, opacity circles -->
  <g opacity=".5" >
    <circle cx="382.5" cy="250" r="50" fill="red" opacity="1"  />
    <circle cx="417.5" cy="250" r="50" fill="green" opacity="1"  />
  </g>
  <!-- Opaque group, semi-transparent green over red -->
  <g opacity="1" >
    <circle cx="582.5" cy="250" r="50" fill="red" opacity=".5"  />
    <circle cx="617.5" cy="250" r="50" fill="green" opacity=".5"  />
  </g>
  <!-- Opaque group, semi-transparent red over green -->
  <g opacity="1" >
    <circle cx="817.5" cy="250" r="50" fill="green" opacity=".5"  />
    <circle cx="782.5" cy="250" r="50" fill="red" opacity=".5"  />
  </g>
  <!-- Group opacity .5, semi-transparent green over red -->
  <g opacity=".5" >
    <circle cx="982.5" cy="250" r="50" fill="red" opacity=".5"  />
    <circle cx="1017.5" cy="250" r="50" fill="green" opacity=".5"  />
  </g>
</svg>

Example opacity01

In the example above, the top row of circles have differing opacities, ranging from 1.0 to 0.2. The bottom row illustrates five ‘g’ елементи, each of which contains overlapping red and green circles, as follows:

The first group shows the opaque case for reference. The group has opacity of 1, as do the circles.
The second group shows group opacity when the елементи in the group are opaque.
The third and fourth group show that opacity is not commutative. In the third group (which has opacity of 1), a semi-transparent green circle is drawn on top of a semi-transparent red circle, whereas in the fourth group a semi-transparent red circle is drawn on top of a semi-transparent green circle. Note that area where the two circles intersect display different colors. The third group shows more green color in the intersection area, whereas the fourth group shows more red color.
The fifth group shows the multiplicative effect of opacity settings. Both the circles and the group itself have opacity settings of .5. The result is that the portion of the red circle which does not overlap with the green circle (i.e., the top/right of the red circle) will blend into the blue rectangle with accumulative opacity of .25 (i.e., .5*.5), which, after blending into the blue rectangle, results in a blended color which is 25% red and 75% blue.

14.6 DOM interfaces

14.6.1 Інтерфейс SVGClipPathElement

The SVGClipPathElement interface corresponds to the ‘clipPath’ елемент.

interface SVGClipPathElement : SVGElement,
                               SVGTests,
                               SVGLangSpace,
                               SVGExternalResourcesRequired,
                               SVGStylable,
                               SVGTransformable,
                               SVGUnitTypes {
  readonly атрибут SVGAnimatedEnumeration clipPathUnits;
};

Attributes:

clipPathUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘clipPathUnits’ on the given ‘clipPath’ елемент. Takes one of the constants defined in SVGUnitTypes.

14.6.2 Інтерфейс SVGMaskElement

The SVGMaskElement interface corresponds to the ‘mask’ елемент.

interface SVGMaskElement : SVGElement,
                           SVGTests,
                           SVGLangSpace,
                           SVGExternalResourcesRequired,
                           SVGStylable,
                           SVGUnitTypes {
  readonly атрибут SVGAnimatedEnumeration maskUnits;
  readonly атрибут SVGAnimatedEnumeration maskContentUnits;
  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
  readonly атрибут SVGAnimatedLength width;
  readonly атрибут SVGAnimatedLength height;
};

Attributes:

maskUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘maskUnits’ on the given ‘mask’ елемент. Takes one of the constants defined in SVGUnitTypes.
maskContentUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘maskContentUnits’ on the given ‘mask’ елемент. Takes one of the constants defined in SVGUnitTypes.
x (readonly SVGAnimatedLength): Corresponds to атрибут ‘x’ on the given ‘mask’ елемент.
y (readonly SVGAnimatedLength): Corresponds to атрибут ‘y’ on the given ‘mask’ елемент.
width (readonly SVGAnimatedLength): Corresponds to атрибут ‘width’ on the given ‘mask’ елемент.
height (readonly SVGAnimatedLength): Corresponds to атрибут ‘height’ on the given ‘mask’ елемент.

15 Filter Effects

15.1 Вступ
15.2 An example
15.3 The ‘filter’ елемент
15.4 The ‘filter’ властивість
15.5 Filter effects region
15.6 Accessing the background image
15.7 Filter primitives overview
- 15.7.1 Огляд
- 15.7.2 Common атрибути
- 15.7.3 Filter primitive subregion
15.8 Light source елементи and властивості
- 15.8.1 Вступ
- 15.8.2 Light source ‘feDistantLight’
- 15.8.3 Light source ‘fePointLight’
- 15.8.4 Light source ‘feSpotLight’
- 15.8.5 The ‘lighting-color’ властивість
15.9 Filter primitive ‘feBlend’
15.10 Filter primitive ‘feColorMatrix’
15.11 Filter primitive ‘feComponentTransfer’
15.12 Filter primitive ‘feComposite’
15.13 Filter primitive ‘feConvolveMatrix’
15.14 Filter primitive ‘feDiffuseLighting’
15.15 Filter primitive ‘feDisplacementMap’
15.16 Filter primitive ‘feFlood’
15.17 Filter primitive ‘feGaussianBlur’
15.18 Filter primitive ‘feImage’
15.19 Filter primitive ‘feMerge’
15.20 Filter primitive ‘feMorphology’
15.21 Filter primitive ‘feOffset’
15.22 Filter primitive ‘feSpecularLighting’
15.23 Filter primitive ‘feTile’
15.24 Filter primitive ‘feTurbulence’
15.25 DOM interfaces
- 15.25.1 Інтерфейс SVGFilterElement
- 15.25.2 Інтерфейс SVGFilterPrimitiveStandardAttributes
- 15.25.3 Інтерфейс SVGFEBlendElement
- 15.25.4 Інтерфейс SVGFEColorMatrixElement
- 15.25.5 Інтерфейс SVGFEComponentTransferElement
- 15.25.6 Інтерфейс SVGComponentTransferFunctionElement
- 15.25.7 Інтерфейс SVGFEFuncRElement
- 15.25.8 Інтерфейс SVGFEFuncGElement
- 15.25.9 Інтерфейс SVGFEFuncBElement
- 15.25.10 Інтерфейс SVGFEFuncAElement
- 15.25.11 Інтерфейс SVGFECompositeElement
- 15.25.12 Інтерфейс SVGFEConvolveMatrixElement
- 15.25.13 Інтерфейс SVGFEDiffuseLightingElement
- 15.25.14 Інтерфейс SVGFEDistantLightElement
- 15.25.15 Інтерфейс SVGFEPointLightElement
- 15.25.16 Інтерфейс SVGFESpotLightElement
- 15.25.17 Інтерфейс SVGFEDisplacementMapElement
- 15.25.18 Інтерфейс SVGFEFloodElement
- 15.25.19 Інтерфейс SVGFEGaussianBlurElement
- 15.25.20 Інтерфейс SVGFEImageElement
- 15.25.21 Інтерфейс SVGFEMergeElement
- 15.25.22 Інтерфейс SVGFEMergeNodeElement
- 15.25.23 Інтерфейс SVGFEMorphologyElement
- 15.25.24 Інтерфейс SVGFEOffsetElement
- 15.25.25 Інтерфейс SVGFESpecularLightingElement
- 15.25.26 Інтерфейс SVGFETileElement
- 15.25.27 Інтерфейс SVGFETurbulenceElement

15.1 Вступ

This chapter describes SVG's declarative filter effects feature set, which when combined with the 2D power of SVG can describe much of the common artwork on the Web in such a way that client-side generation and alteration can be performed easily. In addition, the ability to apply filter effects to SVG graphics елементи and container елементи helps to maintain the semantic structure of the document, instead of resorting to images which aside from generally being a fixed resolution tend to obscure the original semantics of the елементи they replace. This is especially true for effects applied to text.

A filter effect consists of a series of graphics operations that are applied to a given source graphic to produce a modified graphical result. The result of the filter effect is rendered to the target device instead of the original source graphic. The following illustrates the process:

Image showing source graphic transformed by filter effect

View this example as SVG (SVG-enabled browsers only)

Filter effects are defined by ‘filter’ елементи. To apply a filter effect to a graphics елемент or a container елемент, you set the value of the ‘filter’ властивість on the given елемент such that it references the filter effect.

Each ‘filter’ елемент contains a set of filter primitives as its children. Each filter primitive performs a single fundamental graphical operation (e.g., a blur or a lighting effect) on one or more inputs, producing a graphical result. Because most of the filter primitives represent some form of image processing, in most cases the output from a filter primitive is a single RGBA image.

The original source graphic or the result from a filter primitive can be used as input into one or more other filter primitives. A common application is to use the source graphic multiple times. For example, a simple filter could replace one graphic by two by adding a black copy of original source graphic offset to create a drop shadow. In effect, there are now two layers of graphics, both with the same original source graphics.

When applied to container елементи such as ‘g’, the ‘filter’ властивість applies to the contents of the group as a whole. The group's children do not render to the screen directly; instead, the graphics commands necessary to render the children are stored temporarily. Typically, the graphics commands are executed as part of the processing of the referenced ‘filter’ елемент via use of the keywords SourceGraphic or SourceAlpha. Filter effects can be applied to container елементи with no content (e.g., an empty ‘g’ елемент), in which case the SourceGraphic or SourceAlpha consist of a transparent black rectangle that is the size of the filter effects region.

Sometimes filter primitives result in undefined pixels. For example, filter primitive ‘feOffset’ can shift an image down and to the right, leaving undefined pixels at the top and left. In these cases, the undefined pixels are set to transparent black.

15.2 An example

The following shows an example of a filter effect.

Example filters01 - introducing filter effects.

<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
              "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="7.5cm" height="5cm" viewBox="0 0 200 120"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example filters01.svg - introducing filter effects</title>
  <desc>An example which combines multiple filter primitives
        to produce a 3D lighting effect on a graphic consisting
        of the string "SVG" sitting on top of oval filled in red
        and surrounded by an oval outlined in red.</desc>
  <defs>
    <filter id="MyFilter" filterUnits="userSpaceOnUse" x="0" y="0" width="200" height="120">
      <feGaussianBlur in="SourceAlpha" stdDeviation="4" result="blur"/>
      <feOffset in="blur" dx="4" dy="4" result="offsetBlur"/>
      <feSpecularLighting in="blur" surfaceScale="5" specularConstant=".75" 
                          specularExponent="20" lighting-color="#bbbbbb"  
                          result="specOut">
        <fePointLight x="-5000" y="-10000" z="20000"/>
      </feSpecularLighting>
      <feComposite in="specOut" in2="SourceAlpha" operator="in" result="specOut"/>
      <feComposite in="SourceGraphic" in2="specOut" operator="arithmetic" 
                   k1="0" k2="1" k3="1" k4="0" result="litPaint"/>
      <feMerge>
        <feMergeNode in="offsetBlur"/>
        <feMergeNode in="litPaint"/>
      </feMerge>
    </filter>
  </defs>
  <rect x="1" y="1" width="198" height="118" fill="#888888" stroke="blue" />
  <g filter="url(#MyFilter)" >
	  <g>
      <path fill="none" stroke="#D90000" stroke-width="10" 
            d="M50,90 C0,90 0,30 50,30 L150,30 C200,30 200,90 150,90 z" />
      <path fill="#D90000" 
            d="M60,80 C30,80 30,40 60,40 L140,40 C170,40 170,80 140,80 z" />
      <g fill="#FFFFFF" stroke="black" font-size="45" font-family="Verdana" >
        <text x="52" y="76">SVG</text>
      </g>
    </g>
  </g>
</svg>

Example filters01

View this example as SVG (SVG-enabled browsers only)

The filter effect used in the example above is repeated here with reference numbers in the left column before each of the six filter primitives:

<filter id="MyFilter" filterUnits="userSpaceOnUse" x="0" y="0" width="200" height="120">
  <desc>Produces a 3D lighting effect.</desc>
  <feGaussianBlur in="SourceAlpha" stdDeviation="4" result="blur"/>
  <feOffset in="blur" dx="4" dy="4" result="offsetBlur"/>
  <feSpecularLighting in="blur" surfaceScale="5" specularConstant=".75" 
                      specularExponent="20" lighting-color="#bbbbbb" 
                      result="specOut">
    <fePointLight x="-5000" y="-10000" z="20000"/>
  </feSpecularLighting>
  <feComposite in="specOut" in2="SourceAlpha" operator="in" result="specOut"/>
  <feComposite in="SourceGraphic" in2="specOut" operator="arithmetic" 
               k1="0" k2="1" k3="1" k4="0" result="litPaint"/>
  <feMerge>
    <feMergeNode in="offsetBlur"/>
    <feMergeNode in="litPaint"/>
  </feMerge>
</filter>

The following pictures show the intermediate image results from each of the six filter елементи:

Source graphic	After filter primitive 1	After filter primitive 2	After filter primitive 3

	After filter primitive 4	After filter primitive 5	After filter primitive 6

Filter primitive ‘feGaussianBlur’ takes input SourceAlpha, which is the alpha channel of the source graphic. The result is stored in a temporary buffer named "blur". Note that "blur" is used as input to both filter primitives 2 and 3.
Filter primitive ‘feOffset’ takes buffer "blur", shifts the result in a positive direction in both x and y, and creates a new buffer named "offsetBlur". The effect is that of a drop shadow.
Filter primitive ‘feSpecularLighting’, uses buffer "blur" as a модель of a surface elevation and generates a lighting effect from a single point source. The result is stored in buffer "specOut".
Filter primitive ‘feComposite’ masks out the result of filter primitive 3 by the original source graphics alpha channel so that the intermediate result is no bigger than the original source graphic.
Filter primitive ‘feComposite’ composites the result of the specular lighting with the original source graphic.
Filter primitive ‘feMerge’ composites two layers together. The lower layer consists of the drop shadow result from filter primitive 2. The upper layer consists of the specular lighting result from filter primitive 5.

The description of the ‘filter’ елемент follows:

‘filter’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘x’
‘y’
‘width’
‘height’
‘filterRes’
‘filterUnits’
‘primitiveUnits’
‘xlink:href’

DOM Інтерфейсs:

SVGFilterElement

Attribute definitions:

filterUnits = "userSpaceOnUse | objectBoundingBox": See Filter effects region.
primitiveUnits = "userSpaceOnUse | objectBoundingBox": Specifies the coordinate system for the various length values within the filter primitives and for the атрибути that define the filter primitive subregion.
If primitiveUnits="userSpaceOnUse", any length values within the filter definitions represent values in the current user coordinate system in place at the time when the ‘filter’ елемент is referenced (i.e., the user coordinate system for the елемент referencing the ‘filter’ елемент via a ‘filter’ властивість).
If primitiveUnits="objectBoundingBox", then any length values within the filter definitions represent fractions or percentages of the bounding box on the referencing елемент (see Object bounding box units). Note that if only one number was specified in a <number-optional-number> value this number is expanded out before the ‘primitiveUnits’ computation takes place.
If атрибут ‘primitiveUnits’ is not specified, then the effect is as if a value of userSpaceOnUse were specified.
Animatable: yes.
x = "<coordinate>": See Filter effects region.
y = "<coordinate>": See Filter effects region.
width = "<length>": See Filter effects region.
height = "<length>": See Filter effects region.
filterRes = "<number-optional-number>": See Filter effects region.
xlink:href = "<iri>": An IRI reference to another ‘filter’ елемент within the current SVG document fragment. Any атрибути which are defined on the referenced ‘filter’ елемент which are not defined on this елемент are inherited by this елемент. If this елемент has no defined filter nodes, and the referenced елемент has defined filter nodes (possibly due to its own ‘xlink:href’ атрибут), then this елемент inherits the filter nodes defined from the referenced ‘filter’ елемент. Inheritance can be indirect to an arbitrary level; thus, if the referenced ‘filter’ елемент inherits атрибути or its filter node specification due to its own ‘xlink:href’ атрибут, then the current елемент can inherit those атрибути or filter node specifications.
Animatable: yes.

Properties inherit into the ‘filter’ елемент from its ancestors; властивості do not inherit from the елемент referencing the ‘filter’ елемент.

‘filter’ елементи are never rendered directly; their only usage is as something that can be referenced using the ‘filter’ властивість. The ‘display’ властивість does not apply to the ‘filter’ елемент; thus, ‘filter’ елементи are not directly rendered even if the ‘display’ властивість is set to a value other than none, and ‘filter’ елементи are available for referencing even when the ‘display’ властивість on the ‘filter’ елемент or any of its ancestors is set to none.

15.4 The ‘filter’ властивість

The description of the ‘filter’ властивість is as follows:

‘filter’

Value:	<funciri> \| none \| inherit
Initial:	none
Applies to:	container елементи (except ‘mask’) and graphics елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

<funciri>: An Functional IRI reference to a ‘filter’ елемент which defines the filter effects that shall be applied to this елемент.
none: Do not apply any filter effects to this елемент.

15.5 Filter effects region

A ‘filter’ елемент can define a region on the canvas to which a given filter effect applies and can provide a resolution for any intermediate continuous tone images used to process any raster-based filter primitives. The ‘filter’ елемент has the following атрибути which work together to define the filter effects region:

‘filterUnits’

Defines the coordinate system for атрибути ‘x’, ‘y’, ‘width’ and ‘height’.

If filterUnits="userSpaceOnUse", ‘x’, ‘y’, ‘width’ and ‘height’ represent values in the current user coordinate system in place at the time when the ‘filter’ is referenced (i.e., the user coordinate system for the елемент referencing the ‘filter’ via a ‘filter’ властивість).

If filterUnits="objectBoundingBox", then ‘x’, ‘y’, ‘width’ and ‘height’ represent fractions or percentages of the bounding box on the referencing елемент (see Object bounding box units).

If атрибут ‘filterUnits’ is not specified, then the effect is if a value of 'objectBoundingBox' were specified.

Animatable: yes.

‘x’, ‘y’, ‘width’ and ‘height’

These атрибути define a rectangular region on the canvas to which this filter applies.

The amount of memory and processing time required to apply the filter are related to the size of this rectangle and the ‘filterRes’ атрибут of the filter.

The coordinate system for these атрибути depends on the value for атрибут ‘filterUnits’.

Negative values for ‘width’ or ‘height’ are an error (see Error processing). Zero values disable rendering of the елемент which referenced the filter.

The bounds of this rectangle act as a hard clipping region for each filter primitive included with a given ‘filter’ елемент; thus, if the effect of a given filter primitive would extend beyond the bounds of the rectangle (this sometimes happens when using a ‘feGaussianBlur’ filter primitive with a very large ‘stdDeviation’), parts of the effect will get clipped.

If ‘x’ or ‘y’ is not specified, the effect is as if a value of -10% were specified.

If ‘width’ or ‘height’ is not specified, the effect is as if a value of 120% were specified.

Animatable: yes.

‘filterRes’

This атрибут takes the form x-pixels [y-pixels], and indicates the width and height of the intermediate images in pixels. If not provided, then the user agent will use reasonable values to produce a high-quality result on the output device.

Care should be taken when assigning a non-default value to this атрибут. Too small of a value may result in unwanted pixelation in the result. Too large of a value may result in slow processing and large memory usage.

Negative values are an error (see Error processing). Zero values disable rendering of the елемент which referenced the filter.

Non-integer values are truncated, i.e rounded to the closest integer value towards zero.

Animatable: yes.

Note that both of the two possible value for ‘filterUnits’ (i.e., 'objectBoundingBox' and 'userSpaceOnUse') result in a filter region whose coordinate system has its X-axis and Y-axis each parallel to the X-axis and Y-axis, respectively, of the user coordinate system for the елемент to which the filter will be applied.

Sometimes implementers can achieve faster performance when the filter region can be mapped directly to device pixels; thus, for best performance on display devices, it is suggested that authors define their region such that SVG user agent can align the filter region pixel-for-pixel with the background. In particular, for best filter effects performance, avoid rotating or skewing the user coordinate system. Explicit values for атрибут ‘filterRes’ can either help or harm performance. If ‘filterRes’ is smaller than the automatic (i.e., default) filter resolution, then filter effect might have faster performance (usually at the expense of quality). If ‘filterRes’ is larger than the automatic (i.e., default) filter resolution, then filter effects performance will usually be slower.

It is often necessary to provide padding space because the filter effect might impact bits slightly outside the tight-fitting bounding box on a given object. For these purposes, it is possible to provide negative percentage values for ‘x’ and ‘y’, and percentages values greater than 100% for ‘width’ and ‘height’. This, for example, is why the defaults for the filter effects region are x="-10%" y="-10%" width="120%" height="120%".

15.6 Accessing the background image

Two possible pseudo input images for filter effects are BackgroundImage and BackgroundAlpha, which each represent an image snapshot of the canvas under the filter region at the time that the ‘filter’ елемент is invoked. BackgroundImage represents both the color values and alpha channel of the canvas (i.e., RGBA pixel values), whereas BackgroundAlpha represents only the alpha channel.

Implementations of SVG user agents often will need to maintain supplemental background image buffers in order to support the BackgroundImage and BackgroundAlpha pseudo input images. Sometimes, the background image buffers will contain an in-memory copy of the accumulated painting operations on the current canvas.

Because in-memory image buffers can take up significant system resources, SVG content must explicitly indicate to the SVG user agent that the document needs access to the background image before BackgroundImage and BackgroundAlpha pseudo input images can be used. The властивість which enables access to the background image is ‘enable-background’, defined below:

‘enable-background’

Value:	accumulate \| new [ <x> <y> <width> <height> ] \| inherit
Initial:	accumulate
Applies to:	container елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	no

‘enable-background’ is only applicable to container елементи and specifies how the SVG user agents manages the accumulation of the background image.

A value of new indicates two things:

It enables the ability of children of the current container елемент to access the background image.
It indicates that a new (i.e., initially transparent black) background image canvas is established and that (in effect) all children of the current container елемент shall be rendered into the new background image canvas in addition to being rendered onto the target device.

A meaning of enable-background: accumulate (the initial/default value) depends on context:

If an ancestor container елемент has a властивість value of enable-background: new, then all graphics елементи within the current container елемент are rendered both onto the parent container елемент's background image canvas and onto the target device.
Otherwise, there is no current background image canvas, so it is only necessary to render graphics елементи onto the target device. (No need to render to the background image canvas.)

If a filter effect specifies either the BackgroundImage or the BackgroundAlpha pseudo input images and no ancestor container елемент has a властивість value of enable-background: new, then the background image request is technically in error. Processing will proceed without interruption (i.e., no error message) and a transparent black image shall be provided in response to the request.

The optional <x>,<y>,<width>,<height> parameters on the new value are <number> values that indicate the subregion of the container елемент's user space where access to the background image is allowed to happen. These parameters enable the SVG user agent potentially to allocate smaller temporary image buffers than the default values. Thus, the values <x>,<y>,<width>,<height> act as a clipping rectangle on the background image canvas. Negative values for <width> or <height> are an error (see Error processing). If more than zero but less than four of the values <x>,<y>,<width> and <height> are specified or if zero values are specified for <width> or <height>, BackgroundImage and BackgroundAlpha are processed as if background image processing were not enabled.

Assume you have an елемент E in the document and that E has a series of ancestors A₁ (its immediate parent), A₂, etc. (Note: A₀ is E.) Each ancestor A_i will have a corresponding temporary background image offscreen buffer BUF_i. The contents of the background image available to a ‘filter’ referenced by E is defined as follows:

Find the елемент A_i with the smallest subscript i (including A₀=E) for which the ‘enable-background’ властивість has the value new. (Note: if there is no such ancestor елемент, then there is no background image available to E, in which case a transparent black image will be used as E's background image.)
For each A_i (from i=n to 1), initialize BUF_i to transparent black. Render all children of A_i up to but not including A_i-1 into BUF_i. The children are painted, then filtered, clipped, masked and composited using the various painting, filtering, clipping, masking and object opacity settings on the given child. Any filter effects, masking and group opacity that might be set on A_i do not apply when rendering the children of A_i into BUF_i.
(Note that for the case of A₀=E, the graphical contents of E are not rendered into BUF₁ and thus are not part of the background image available to E. Instead, the graphical contents of E are available via the SourceGraphic and SourceAlpha pseudo input images.)
Then, for each A_i (from i=1 to n-1), composite BUF_i into BUF_i+1.
The accumulated result (i.e., BUF_n) represents the background image available to E.

Example enable-background-01 illustrates the rules for background image processing.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="13.5cm" height="2.7cm" viewBox="0 0 1350 270"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example enable-background01</title>
  <desc>This test case shows five pictures which illustrate the rules
        for background image processing.</desc>

  <defs>
    <filter id="ShiftBGAndBlur" 
            filterUnits="userSpaceOnUse" x="0" y="0" width="1200" height="400">
      <desc>
        This filter discards the SourceGraphic, if any, and just produces
        a result consisting of the BackgroundImage shifted down 125 units
        and then blurred.
      </desc>
      <feOffset in="BackgroundImage" dx="0" dy="125" />
      <feGaussianBlur stdDeviation="8" />
    </filter>
    <filter id="ShiftBGAndBlur_WithSourceGraphic" 
            filterUnits="userSpaceOnUse" x="0" y="0" width="1200" height="400">
      <desc>
        This filter takes the BackgroundImage, shifts it down 125 units, blurs it,
        and then renders the SourceGraphic on top of the shifted/blurred background.
      </desc>
      <feOffset in="BackgroundImage" dx="0" dy="125" />
      <feGaussianBlur stdDeviation="8" result="blur" />
      <feMerge>
        <feMergeNode in="blur"/>
        <feMergeNode in="SourceGraphic"/>
      </feMerge>
    </filter>
  </defs>

  <g transform="translate(0,0)">
    <desc>The first picture is our reference graphic without filters.</desc>
    <rect x="25" y="25" width="100" height="100" fill="red"/>
    <g opacity=".5">
      <circle cx="125" cy="75" r="45" fill="green"/>
      <polygon points="160,25 160,125 240,75" fill="blue"/>
    </g>
    <rect x="5" y="5" width="260" height="260" fill="none" stroke="blue"/>
  </g>

  <g enable-background="new" transform="translate(270,0)">
    <desc>The second adds an empty 'g' елемент which invokes ShiftBGAndBlur.</desc>
    <rect x="25" y="25" width="100" height="100" fill="red"/>
    <g opacity=".5">
      <circle cx="125" cy="75" r="45" fill="green"/>
      <polygon points="160,25 160,125 240,75" fill="blue"/>
    </g>
    <g filter="url(#ShiftBGAndBlur)"/>
    <rect x="5" y="5" width="260" height="260" fill="none" stroke="blue"/>
  </g>

  <g enable-background="new" transform="translate(540,0)">
    <desc>The third invokes ShiftBGAndBlur on the inner group.</desc>
    <rect x="25" y="25" width="100" height="100" fill="red"/>
    <g filter="url(#ShiftBGAndBlur)" opacity=".5">
      <circle cx="125" cy="75" r="45" fill="green"/>
      <polygon points="160,25 160,125 240,75" fill="blue"/>
    </g>
    <rect x="5" y="5" width="260" height="260" fill="none" stroke="blue"/>
  </g>

  <g enable-background="new" transform="translate(810,0)">
    <desc>The fourth invokes ShiftBGAndBlur on the triangle.</desc>
    <rect x="25" y="25" width="100" height="100" fill="red"/>
    <g opacity=".5">
      <circle cx="125" cy="75" r="45" fill="green"/>
      <polygon points="160,25 160,125 240,75" fill="blue"
               filter="url(#ShiftBGAndBlur)"/>
    </g>
    <rect x="5" y="5" width="260" height="260" fill="none" stroke="blue"/>
  </g>

  <g enable-background="new" transform="translate(1080,0)">
    <desc>The fifth invokes ShiftBGAndBlur_WithSourceGraphic on the triangle.</desc>
    <rect x="25" y="25" width="100" height="100" fill="red"/>
    <g opacity=".5">
      <circle cx="125" cy="75" r="45" fill="green"/>
      <polygon points="160,25 160,125 240,75" fill="blue"
               filter="url(#ShiftBGAndBlur_WithSourceGraphic)"/>
    </g>
    <rect x="5" y="5" width="260" height="260" fill="none" stroke="blue"/>
  </g>
</svg>

Example enable-background-01

View this example as SVG (SVG-enabled browsers only)

The example above contains five parts, described as follows:

The first set is the reference graphic. The reference graphic consists of a red rectangle followed by a 50% transparent ‘g’ елемент. Inside the ‘g’ is a green circle that partially overlaps the rectangle and a a blue triangle that partially overlaps the circle. The three objects are then outlined by a rectangle stroked with a thin blue line. No filters are applied to the reference graphic.
The second set enables background image processing and adds an empty ‘g’ елемент which invokes the ShiftBGAndBlur filter. This filter takes the current accumulated background image (i.e., the entire reference graphic) as input, shifts its offscreen down, blurs it, and then writes the result to the canvas. Note that the offscreen for the filter is initialized to transparent black, which allows the already rendered rectangle, circle and triangle to show through after the filter renders its own result to the canvas.
The third set enables background image processing and instead invokes the ShiftBGAndBlur filter on the inner ‘g’ елемент. The accumulated background at the time the filter is applied contains only the red rectangle. Because the children of the inner ‘g’ (i.e., the circle and triangle) are not part of the inner ‘g’ елемент's background and because ShiftBGAndBlur ignores SourceGraphic, the children of the inner ‘g’ do not appear in the result.
The fourth set enables background image processing and invokes the ShiftBGAndBlur on the ‘polygon’ елемент that draws the triangle. The accumulated background at the time the filter is applied contains the red rectangle plus the green circle ignoring the effect of the ‘opacity’ властивість on the inner ‘g’ елемент. (Note that the blurred green circle at the bottom does not let the red rectangle show through on its left side. This is due to ignoring the effect of the ‘opacity’ властивість.) Because the triangle itself is not part of the accumulated background and because ShiftBGAndBlur ignores SourceGraphic, the triangle does not appear in the result.
The fifth set is the same as the fourth except that filter ShiftBGAndBlur_WithSourceGraphic is invoked instead of ShiftBGAndBlur. ShiftBGAndBlur_WithSourceGraphic performs the same effect as ShiftBGAndBlur, but then renders the SourceGraphic on top of the shifted, blurred background image. In this case, SourceGraphic is the blue triangle; thus, the result is the same as in the fourth case except that the blue triangle now appears.

15.7 Filter primitives overview

15.7.1 Огляд

This section describes the various filter primtives that can be assembled to achieve a particular filter effect.

Unless otherwise stated, all image filters operate on premultiplied RGBA samples. Filters which work more naturally on non-premultiplied data (feColorMatrix and feComponentTransfer) will temporarily undo and redo premultiplication as specified. All raster effect filtering operations take 1 to N input RGBA images, additional атрибути as parameters, and produce a single output RGBA image.

The RGBA result from each filter primitive will be clamped into the allowable ranges for colors and opacity values. Thus, for example, the result from a given filter primitive will have any negative color values or opacity values adjusted up to color/opacity of zero.

The color space in which a particular filter primitive performs its operations is determined by the value of властивість ‘color-interpolation-filters’ on the given filter primitive. A different властивість, ‘color-interpolation’ determines the color space for other color operations. Because these two властивості have different initial values (‘color-interpolation-filters’ has an initial value of linearRGB whereas ‘color-interpolation’ has an initial value of sRGB), in some cases to achieve certain results (e.g., when coordinating gradient interpolation with a filtering operation) it will be necessary to explicitly set ‘color-interpolation’ to linearRGB or ‘color-interpolation-filters’ to sRGB on particular елементи. Note that the examples below do not explicitly set either ‘color-interpolation’ or ‘color-interpolation-filters’, so the initial values for these властивості apply to the examples.

15.7.2 Common атрибути

With the exception of the ‘in’ атрибут, all of the following атрибути are available on all filter primitive елементи:

Attribute definitions:

x = "<coordinate>"

The minimum x coordinate for the subregion which restricts calculation and rendering of the given filter primitive. See filter primitive subregion.
Animatable: yes.

y = "<coordinate>"

The minimum y coordinate for the subregion which restricts calculation and rendering of the given filter primitive. See filter primitive subregion.
Animatable: yes.

width = "<length>"

The width of the subregion which restricts calculation and rendering of the given filter primitive. See filter primitive subregion.
A negative value is an error (see Error processing). A value of zero disables the effect of the given filter primitive (i.e., the result is a transparent black image).
Animatable: yes.

height = "<length>"

The height of the subregion which restricts calculation and rendering of the given filter primitive. See filter primitive subregion.
A negative value is an error (see Error processing). A value of zero disables the effect of the given filter primitive (i.e., the result is a transparent black image).
Animatable: yes.

result = "<filter-primitive-reference>"

Assigned name for this filter primitive. If supplied, then graphics that result from processing this filter primitive can be referenced by an ‘in’ атрибут on a subsequent filter primitive within the same ‘filter’ елемент. If no value is provided, the output will only be available for re-use as the implicit input into the next filter primitive if that filter primitive provides no value for its ‘in’ атрибут.
Note that a <filter-primitive-reference> is not an XML ID; instead, a <filter-primitive-reference> is only meaningful within a given ‘filter’ елемент and thus have only local scope. It is legal for the same <filter-primitive-reference> to appear multiple times within the same ‘filter’ елемент. When referenced, the <filter-primitive-reference> will use the closest preceding filter primitive with the given result.
Animatable: yes.

Identifies input for the given filter primitive. The value can be either one of six keywords or can be a string which matches a previous ‘result’ атрибут value within the same ‘filter’ елемент. If no value is provided and this is the first filter primitive, then this filter primitive will use SourceGraphic as its input. If no value is provided and this is a subsequent filter primitive, then this filter primitive will use the result from the previous filter primitive as its input.

If the value for ‘result’ appears multiple times within a given ‘filter’ елемент, then a reference to that result will use the closest preceding filter primitive with the given value for атрибут ‘result’. Forward references to results are an error.

Визначення for the six keywords:

SourceGraphic: This keyword represents the graphics елементи that were the original input into the ‘filter’ елемент. For raster effects filter primitives, the graphics елементи will be rasterized into an initially clear RGBA raster in image space. Pixels left untouched by the original graphic will be left clear. The image is specified to be rendered in linear RGBA pixels. The alpha channel of this image captures any anti-aliasing specified by SVG. (Since the raster is linear, the alpha channel of this image will represent the exact percent coverage of each pixel.)
SourceAlpha: This keyword represents the graphics елементи that were the original input into the ‘filter’ елемент. SourceAlpha has all of the same rules as SourceGraphic except that only the alpha channel is used. The input image is an RGBA image consisting of implicitly black color values for the RGB channels, but whose alpha channel is the same as SourceGraphic. If this option is used, then some implementations might need to rasterize the graphics елементи in order to extract the alpha channel.
BackgroundImage: This keyword represents an image snapshot of the canvas under the filter region at the time that the ‘filter’ елемент was invoked. See Accessing the background image.
BackgroundAlpha: Same as BackgroundImage except only the alpha channel is used. See SourceAlpha and Accessing the background image.
FillPaint: This keyword represents the value of the ‘fill’ властивість on the target елемент for the filter effect. The FillPaint image has conceptually infinite extent. Frequently this image is opaque everywhere, but it might not be if the "paint" itself has alpha, as in the case of a gradient or pattern which itself includes transparent or semi-transparent parts.
StrokePaint: This keyword represents the value of the ‘stroke’ властивість on the target елемент for the filter effect. The StrokePaint image has conceptually infinite extent. Frequently this image is opaque everywhere, but it might not be if the "paint" itself has alpha, as in the case of a gradient or pattern which itself includes transparent or semi-transparent parts.

The ‘in’ атрибут is available on all filter primitive елементи that require an input.

Animatable: yes.

15.7.3 Filter primitive subregion

All filter primitives have атрибути ‘x’, ‘y’, ‘width’ and ‘height’ which identify a subregion which restricts calculation and rendering of the given filter primitive. These атрибути are defined according to the same rules as other filter primitives' coordinate and length атрибути and thus represent values in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.

‘x’, ‘y’, ‘width’ and ‘height’ default to the union (i.e., tightest fitting bounding box) of the subregions defined for all referenced nodes. If there are no referenced nodes (e.g., for ‘feImage’ or ‘feTurbulence’), or one or more of the referenced nodes is a standard input (one of SourceGraphic, SourceAlpha, BackgroundImage, BackgroundAlpha, FillPaint or StrokePaint), or for ‘feTile’ (which is special because its principal function is to replicate the referenced node in X and Y and thereby produce a usually larger result), the default subregion is 0%,0%,100%,100%, where as a special-case the percentages are relative to the dimensions of the filter region, thus making the the default filter primitive subregion equal to the filter region.

‘x’, ‘y’, ‘width’ and ‘height’ act as a hard clip clipping rectangle on both the filter primitive's input image(s) and the filter primitive result.

All intermediate offscreens are defined to not exceed the intersection of ‘x’, ‘y’, ‘width’ and ‘height’ with the filter region. The filter region and any of the ‘x’, ‘y’, ‘width’ and ‘height’ subregions are to be set up such that all offscreens are made big enough to accommodate any pixels which even partly intersect with either the filter region or the x,y,width,height subregions.

‘feTile’ references a previous filter primitive and then stitches the tiles together based on the ‘x’, ‘y’, ‘width’ and ‘height’ values of the referenced filter primitive in order to fill its own filter primitive subregion.

Example primitive-subregion-01 demonstrates the effect of specifying a filter primitive subregion:

<svg width="400" height="400" xmlns="http://www.w3.org/2000/svg"> 
  <defs>
    <filter id="flood" x="0" y="0" width="100%" height="100%" primitiveUnits="objectBoundingBox">
       <feFlood x="25%" y="25%" width="50%" height="50%"
          flood-color="green" flood-opacity="0.75"/>
    </filter>
    <filter id="blend" primitiveUnits="objectBoundingBox">
       <feBlend x="25%" y="25%" width="50%" height="50%"
          in2="SourceGraphic" mode="multiply"/>
    </filter>
    <filter id="merge" primitiveUnits="objectBoundingBox">
       <feMerge x="25%" y="25%" width="50%" height="50%">
        <feMergeNode in="SourceGraphic"/>
        <feMergeNode in="FillPaint"/>
       </feMerge>
    </filter>
  </defs>
  
  <g fill="none" stroke="blue" stroke-width="4">
     <rect width="200" height="200"/>
     <line x2="200" y2="200"/>
     <line x1="200" y2="200"/>
  </g>
  <circle fill="green" filter="url(#flood)" cx="100" cy="100" r="90"/>

  <g transform="translate(200 0)">
    <g fill="none" stroke="blue" stroke-width="4">
       <rect width="200" height="200"/>
       <line x2="200" y2="200"/>
       <line x1="200" y2="200"/>
    </g>
    <circle fill="green" filter="url(#blend)" cx="100" cy="100" r="90"/>
  </g>
  
  <g transform="translate(0 200)">
    <g fill="none" stroke="blue" stroke-width="4">
       <rect width="200" height="200"/>
       <line x2="200" y2="200"/>
       <line x1="200" y2="200"/>
    </g>
    <circle fill="green" fill-opacity="0.5" filter="url(#merge)" cx="100" cy="100" r="90"/>
  </g>
</svg>

Example primitive-subregion-01

View this example as SVG (SVG-enabled browsers only)

In the example above there are three rects that each have a cross and a circle in them. The circle елемент in each one has a different filter applied, but with the same filter primitive subregion. The filter output should be limited to the filter primitive subregion, so you should never see the circles themselves, just the rects that make up the filter primitive subregion.

The upper left rect shows an ‘feFlood’ with flood-opacity="75%" so the cross should be visible through the green rect in the middle.
The lower left rect shows an ‘feMerge’ that merges SourceGraphic with FillPaint. Since the circle has fill-opacity="0.5" it will also be transparent so that the cross is visible through the green rect in the middle.
The upper right rect shows an ‘feBlend’ that has mode="multiply". Since the circle in this case isn't transparent the result is totally opaque. The rect should be dark green and the cross should not be visible through it.

15.8 Light source елементи and властивості

15.8.1 Вступ

The following sections define the елементи that define a light source, ‘feDistantLight’, ‘fePointLight’ and ‘feSpotLight’, and властивість ‘lighting-color’, which defines the color of the light.

15.8.2 Light source ‘feDistantLight’

‘feDistantLight’

Categories:

Light source елемент

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
‘azimuth’
‘elevation’

DOM Інтерфейсs:

SVGFEDistantLightElement

Attribute definitions:

azimuth = "<number>": Direction angle for the light source on the XY plane (clockwise), in degrees from the x axis.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
elevation = "<number>": Direction angle for the light source from the XY plane towards the z axis, in degrees. Note the positive Z-axis points towards the viewer of the content.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.

The following diagram illustrates the angles which ‘azimuth’ and ‘elevation’ represent in an XYZ coordinate system.

15.8.3 Light source ‘fePointLight’

‘fePointLight’

Categories:

Light source елемент

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
‘x’
‘y’
‘z’

DOM Інтерфейсs:

SVGFEPointLightElement

Attribute definitions:

x = "<number>": X location for the light source in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
y = "<number>": Y location for the light source in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
z = "<number>": Z location for the light source in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент, assuming that, in the initial coordinate system, the positive Z-axis comes out towards the person viewing the content and assuming that one unit along the Z-axis equals one unit in X and Y.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.

15.8.4 Light source ‘feSpotLight’

‘feSpotLight’

Categories:

Light source елемент

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
‘x’
‘y’
‘z’
‘pointsAtX’
‘pointsAtY’
‘pointsAtZ’
‘specularExponent’
‘limitingConeAngle’

DOM Інтерфейсs:

SVGFESpotLightElement

Attribute definitions:

x = "<number>": X location for the light source in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
y = "<number>": Y location for the light source in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
z = "<number>": Z location for the light source in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент, assuming that, in the initial coordinate system, the positive Z-axis comes out towards the person viewing the content and assuming that one unit along the Z-axis equals one unit in X and Y.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
pointsAtX = "<number>": X location in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент of the point at which the light source is pointing.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
pointsAtY = "<number>": Y location in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент of the point at which the light source is pointing.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
pointsAtZ = "<number>": Z location in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент of the point at which the light source is pointing, assuming that, in the initial coordinate system, the positive Z-axis comes out towards the person viewing the content and assuming that one unit along the Z-axis equals one unit in X and Y.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
specularExponent = "<number>": Exponent value controlling the focus for the light source.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.
limitingConeAngle = "<number>": A limiting cone which restricts the region where the light is projected. No light is projected outside the cone. ‘limitingConeAngle’ represents the angle in degrees between the spot light axis (i.e. the axis between the light source and the point to which it is pointing at) and the spot light cone. User agents should apply a smoothing technique such as anti-aliasing at the boundary of the cone.
If no value is specified, then no limiting cone will be applied.
Animatable: yes.

15.8.5 The ‘lighting-color’ властивість

The ‘lighting-color’ властивість defines the color of the light source for filter primitives ‘feDiffuseLighting’ and ‘feSpecularLighting’.

‘lighting-color’

Value:	currentColor \| <color> [<icccolor>] \| inherit
Initial:	white
Applies to:	‘feDiffuseLighting’ and ‘feSpecularLighting’ елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

15.9 Filter primitive ‘feBlend’

This filter composites two objects together using commonly used imaging software blending modes. It performs a pixel-wise combination of two input images.

‘feBlend’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘in2’
‘mode’

DOM Інтерфейсs:

SVGFEBlendElement

Attribute definitions:

mode = "normal | multiply | screen | darken | lighten": One of the image blending modes (see table below). If атрибут ‘mode’ is not specified, then the effect is as if a value of normal were specified.
Animatable: yes.
in2 = "(see ‘in’ атрибут)": The second input image to the blending operation. This атрибут can take on the same values as the ‘in’ атрибут.
Animatable: yes.

For all feBlend modes, the result opacity is computed as follows:

qr = 1 - (1-qa)*(1-qb)

For the compositing formulas below, the following definitions apply:

cr = Result color (RGB) - premultiplied 
qa = Opacity value at a given pixel for image A 
qb = Opacity value at a given pixel for image B 
ca = Color (RGB) at a given pixel for image A - premultiplied 
cb = Color (RGB) at a given pixel for image B - premultiplied

The following table provides the list of available image blending modes:

Image Blending Mode	Formula for computing result color
normal	cr = (1 - qa) * cb + ca
multiply	cr = (1-qa)cb + (1-qb)ca + ca*cb
screen	cr = cb + ca - ca * cb
darken	cr = Min ((1 - qa) * cb + ca, (1 - qb) * ca + cb)
lighten	cr = Max ((1 - qa) * cb + ca, (1 - qb) * ca + cb)

'normal' blend mode is equivalent to operator="over" on the ‘feComposite’ filter primitive, matches the blending method used by ‘feMerge’ and matches the simple alpha compositing technique used in SVG for all compositing outside of filter effects.

Example feBlend shows examples of the five blend modes.

<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
          "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="5cm" height="5cm" viewBox="0 0 500 500"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example feBlend - Examples of feBlend modes</title>
  <desc>Five text strings blended into a gradient,
        with one text string for each of the five feBlend modes.</desc>
  <defs>
    <linearGradient id="MyGradient" gradientUnits="userSpaceOnUse"
            x1="100" y1="0" x2="300" y2="0">
      <stop offset="0" stop-color="#000000" />
      <stop offset=".33" stop-color="#ffffff" />
      <stop offset=".67" stop-color="#ff0000" />
      <stop offset="1" stop-color="#808080" />
    </linearGradient>
    <filter id="Normal">
      <feBlend mode="normal" in2="BackgroundImage" in="SourceGraphic"/>
    </filter>
    <filter id="Multiply">
      <feBlend mode="multiply" in2="BackgroundImage" in="SourceGraphic"/>
    </filter>
    <filter id="Screen">
      <feBlend mode="screen" in2="BackgroundImage" in="SourceGraphic"/>
    </filter>
    <filter id="Darken">
      <feBlend mode="darken" in2="BackgroundImage" in="SourceGraphic"/>
    </filter>
    <filter id="Lighten">
      <feBlend mode="lighten" in2="BackgroundImage" in="SourceGraphic"/>
    </filter>
  </defs>
  <rect fill="none" stroke="blue"  
        x="1" y="1" width="498" height="498"/>
  <g enable-background="new" >
    <rect x="100" y="20" width="300" height="460" fill="url(#MyGradient)" />
    <g font-family="Verdana" font-size="75" fill="#888888" fill-opacity=".6" >
      <text x="50" y="90" filter="url(#Normal)" >Normal</text>
      <text x="50" y="180" filter="url(#Multiply)" >Multiply</text>
      <text x="50" y="270" filter="url(#Screen)" >Screen</text>
      <text x="50" y="360" filter="url(#Darken)" >Darken</text>
      <text x="50" y="450" filter="url(#Lighten)" >Lighten</text>
    </g>
  </g>
</svg>

Example feBlend

15.10 Filter primitive ‘feColorMatrix’

This filter applies a matrix transformation:

| R' |     | a00 a01 a02 a03 a04 |   | R |
| G' |     | a10 a11 a12 a13 a14 |   | G |
| B' |  =  | a20 a21 a22 a23 a24 | * | B |
| A' |     | a30 a31 a32 a33 a34 |   | A |
| 1  |     |  0   0   0   0   1  |   | 1 |

on the RGBA color and alpha values of every pixel on the input graphics to produce a result with a new set of RGBA color and alpha values.

These matrices often perform an identity mapping in the alpha channel. If that is the case, an implementation can avoid the costly undoing and redoing of the premultiplication for all pixels with A = 1.

‘feColorMatrix’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘type’
‘values’

DOM Інтерфейсs:

SVGFEColorMatrixElement

Attribute definitions:

type = "matrix | saturate | hueRotate | luminanceToAlpha"

Indicates the type of matrix operation. The keyword 'matrix' indicates that a full 5x4 matrix of values will be provided. The other keywords represent convenience shortcuts to allow commonly used color operations to be performed without specifying a complete matrix. If атрибут ‘type’ is not specified, then the effect is as if a value of matrix were specified.
Animatable: yes.

values = "list of <number>s"

The contents of ‘values’ depends on the value of атрибут ‘type’:

For type="matrix", ‘values’ is a list of 20 matrix values (a00 a01 a02 a03 a04 a10 a11 ... a34), separated by whitespace and/or a comma. For example, the identity matrix could be expressed as:
```
type="matrix" 
values="1 0 0 0 0  0 1 0 0 0  0 0 1 0 0  0 0 0 1 0"
```

For type="saturate", ‘values’ is a single real number value (0 to 1). A saturate operation is equivalent to the following matrix operation:

| R' |     |0.213+0.787s  0.715-0.715s  0.072-0.072s 0  0 |   | R |
| G' |     |0.213-0.213s  0.715+0.285s  0.072-0.072s 0  0 |   | G |
| B' |  =  |0.213-0.213s  0.715-0.715s  0.072+0.928s 0  0 | * | B |
| A' |     |           0            0             0  1  0 |   | A |
| 1  |     |           0            0             0  0  1 |   | 1 |

For type="hueRotate", ‘values’ is a single one real number value (degrees). A hueRotate operation is equivalent to the following matrix operation:

| R' |     | a00  a01  a02  0  0 |   | R |
| G' |     | a10  a11  a12  0  0 |   | G |
| B' |  =  | a20  a21  a22  0  0 | * | B |
| A' |     | 0    0    0    1  0 |   | A |
| 1  |     | 0    0    0    0  1 |   | 1 |

where the terms a00, a01, etc. are calculated as follows:

| a00 a01 a02 |    [+0.213 +0.715 +0.072]
| a10 a11 a12 | =  [+0.213 +0.715 +0.072] +
| a20 a21 a22 |    [+0.213 +0.715 +0.072]
                        [+0.787 -0.715 -0.072]
cos(hueRotate value) *  [-0.213 +0.285 -0.072] +
                        [-0.213 -0.715 +0.928]
                        [-0.213 -0.715+0.928]
sin(hueRotate value) *  [+0.143 +0.140-0.283]
                        [-0.787 +0.715+0.072]

Thus, the upper left term of the hue matrix turns out to be:

.213 + cos(hueRotate value)*.787 - sin(hueRotate value)*.213

For type="luminanceToAlpha", ‘values’ is not applicable. A luminanceToAlpha operation is equivalent to the following matrix operation:

   | R' |     |      0        0        0  0  0 |   | R |
   | G' |     |      0        0        0  0  0 |   | G |
   | B' |  =  |      0        0        0  0  0 | * | B |
   | A' |     | 0.2125   0.7154   0.0721  0  0 |   | A |
   | 1  |     |      0        0        0  0  1 |   | 1 |

If the атрибут is not specified, then the default behavior depends on the value of атрибут ‘type’. If type="matrix", then this атрибут defaults to the identity matrix. If type="saturate", then this атрибут defaults to the value 1, which results in the identity matrix. If type="hueRotate", then this атрибут defaults to the value 0, which results in the identity matrix.
Animatable: yes.

Example feColorMatrix shows examples of the four types of feColorMatrix operations.

<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
          "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="8cm" height="5cm" viewBox="0 0 800 500"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example feColorMatrix - Examples of feColorMatrix operations</title>
  <desc>Five text strings showing the effects of feColorMatrix: 
        an unfiltered text string acting as a reference, 
        use of the feColorMatrix matrix option to convert to grayscale,
        use of the feColorMatrix saturate option,
        use of the feColorMatrix hueRotate option,
        and use of the feColorMatrix luminanceToAlpha option.</desc>
  <defs>
    <linearGradient id="MyGradient" gradientUnits="userSpaceOnUse"
            x1="100" y1="0" x2="500" y2="0">
      <stop offset="0" stop-color="#ff00ff" />
      <stop offset=".33" stop-color="#88ff88" />
      <stop offset=".67" stop-color="#2020ff" />
      <stop offset="1" stop-color="#d00000" />
    </linearGradient>
    <filter id="Matrix" filterUnits="objectBoundingBox" 
            x="0%" y="0%" width="100%" height="100%">
      <feColorMatrix type="matrix" in="SourceGraphic"
           values=".33 .33 .33 0 0 
                   .33 .33 .33 0 0 
                   .33 .33 .33 0 0 
                   .33 .33 .33 0 0"/>
    </filter>
    <filter id="Saturate40" filterUnits="objectBoundingBox" 
            x="0%" y="0%" width="100%" height="100%">
      <feColorMatrix type="saturate" in="SourceGraphic" values="0.4"/>
    </filter>
    <filter id="HueRotate90" filterUnits="objectBoundingBox" 
            x="0%" y="0%" width="100%" height="100%">
      <feColorMatrix type="hueRotate" in="SourceGraphic" values="90"/>
    </filter>
    <filter id="LuminanceToAlpha" filterUnits="objectBoundingBox" 
            x="0%" y="0%" width="100%" height="100%">
      <feColorMatrix type="luminanceToAlpha" in="SourceGraphic" result="a"/>
      <feComposite in="SourceGraphic" in2="a" operator="in" />
    </filter>
  </defs>
  <rect fill="none" stroke="blue"  
        x="1" y="1" width="798" height="498"/>
  <g font-family="Verdana" font-size="75" 
            font-weight="bold" fill="url(#MyGradient)" >
    <rect x="100" y="0" width="500" height="20" />
    <text x="100" y="90">Unfiltered</text>
    <text x="100" y="190" filter="url(#Matrix)" >Matrix</text>
    <text x="100" y="290" filter="url(#Saturate40)" >Saturate</text>
    <text x="100" y="390" filter="url(#HueRotate90)" >HueRotate</text>
    <text x="100" y="490" filter="url(#LuminanceToAlpha)" >Luminance</text>
  </g>
</svg>

Example feColorMatrix

15.11 Filter primitive ‘feComponentTransfer’

This filter primitive performs component-wise remapping of data as follows:

R' = feFuncR( R )
G' = feFuncG( G )
B' = feFuncB( B )
A' = feFuncA( A )

for every pixel. It allows operations like brightness adjustment, contrast adjustment, color balance or thresholding.

The calculations are performed on non-premultiplied color values. If the input graphics consists of premultiplied color values, those values are automatically converted into non-premultiplied color values for this operation. (Note that the undoing and redoing of the premultiplication can be avoided if feFuncA is the identity transform and all alpha values on the source graphic are set to 1.)

‘feComponentTransfer’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

‘feFuncA’
‘feFuncB’
‘feFuncG’
‘feFuncR’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’

DOM Інтерфейсs:

SVGFEComponentTransferElement

The child елементи of a ‘feComponentTransfer’ елемент specify the transfer functions for the four channels:

‘feFuncR’ — transfer function for the red component of the input graphic
‘feFuncG’ — transfer function for the green component of the input graphic
‘feFuncB’ — transfer function for the blue component of the input graphic
‘feFuncA’ — transfer function for the alpha component of the input graphic

The following rules apply to the processing of the ‘feComponentTransfer’ елемент:

If more than one transfer function елемент of the same kind is specified, the last occurrence is to be used.
If any of the transfer function елементи are unspecified, the ‘feComponentTransfer’ must be processed as if those transfer function елементи were specified with their ‘type’ атрибути set to 'identity'.

‘feFuncR’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
transfer function елемент атрибути — ‘type’, ‘tableValues’, ‘slope’, ‘intercept’, ‘amplitude’, ‘exponent’, ‘offset’

DOM Інтерфейсs:

SVGFEFuncRElement

‘feFuncG’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
transfer function елемент атрибути — ‘type’, ‘tableValues’, ‘slope’, ‘intercept’, ‘amplitude’, ‘exponent’, ‘offset’

DOM Інтерфейсs:

SVGFEFuncGElement

‘feFuncB’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
transfer function елемент атрибути — ‘type’, ‘tableValues’, ‘slope’, ‘intercept’, ‘amplitude’, ‘exponent’, ‘offset’

DOM Інтерфейсs:

SVGFEFuncBElement

‘feFuncA’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
transfer function елемент атрибути — ‘type’, ‘tableValues’, ‘slope’, ‘intercept’, ‘amplitude’, ‘exponent’, ‘offset’

DOM Інтерфейсs:

SVGFEFuncAElement

The атрибути below are the transfer function елемент атрибути, which apply to sub-елементи ‘feFuncR’, ‘feFuncG’, ‘feFuncB’ and ‘feFuncA’ that define the transfer functions.

Attribute definitions:

type = "identity | table | discrete | linear | gamma"

Indicates the type of component transfer function. The type of function determines the applicability of the other атрибути.

In the following, C is the initial component (e.g., ‘feFuncR’), C' is the remapped component; both in the closed interval [0,1].

For identity:
```
C' = C
```
For table, the function is defined by linear interpolation between values given in the атрибут ‘tableValues’. The table has n+1 values (i.e., v₀ to v_n) specifying the start and end values for n evenly sized interpolation regions. Interpolations use the following formula:
For a value C < 1 find k such that:

k/n <= C < (k+1)/n

The result C' is given by:

C' = v_k + (C - k/n)*n * (v_k+1 - v_k)

If C = 1 then:

C' = v_n.
For discrete, the function is defined by the step function given in the атрибут ‘tableValues’, which provides a list of n values (i.e., v₀ to v_n-1) in order to identify a step function consisting of n steps. The step function is defined by the following formula:
For a value C < 1 find k such that:

k/n <= C < (k+1)/n

The result C' is given by:

C' = v_k

If C = 1 then:

C' = v_n-1.
For linear, the function is defined by the following linear equation:
C' = slope * C + intercept
For gamma, the function is defined by the following exponential function:
C' = amplitude * pow(C, exponent) + offset

Animatable: yes.

tableValues = "(list of <number>s)"

When type="table", the list of <number>s v0,v1,...vn, separated by white space and/or a comma, which define the lookup table. An empty list results in an identity transfer function. If the атрибут is not specified, then the effect is as if an empty list were provided.
Animatable: yes.

slope = "<number>"

When type="linear", the slope of the linear function.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.

intercept = "<number>"

When type="linear", the intercept of the linear function.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.

amplitude = "<number>"

When type="gamma", the amplitude of the gamma function.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.

exponent = "<number>"

When type="gamma", the exponent of the gamma function.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.

offset = "<number>"

When type="gamma", the offset of the gamma function.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.

Example feComponentTransfer shows examples of the four types of feComponentTransfer operations.

<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
          "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="8cm" height="4cm" viewBox="0 0 800 400"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example feComponentTransfer - Examples of feComponentTransfer operations</title>
  <desc>Four text strings showing the effects of feComponentTransfer: 
        an identity function acting as a reference, 
        use of the feComponentTransfer table option,
        use of the feComponentTransfer linear option,
        and use of the feComponentTransfer gamma option.</desc>
  <defs>
    <linearGradient id="MyGradient" gradientUnits="userSpaceOnUse"
            x1="100" y1="0" x2="600" y2="0">
      <stop offset="0" stop-color="#ff0000" />
      <stop offset=".33" stop-color="#00ff00" />
      <stop offset=".67" stop-color="#0000ff" />
      <stop offset="1" stop-color="#000000" />
    </linearGradient>
    <filter id="Identity" filterUnits="objectBoundingBox" 
            x="0%" y="0%" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="identity"/>
        <feFuncG type="identity"/>
        <feFuncB type="identity"/>
        <feFuncA type="identity"/>
      </feComponentTransfer>
    </filter>
    <filter id="Table" filterUnits="objectBoundingBox" 
            x="0%" y="0%" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="table" tableValues="0 0 1 1"/>
        <feFuncG type="table" tableValues="1 1 0 0"/>
        <feFuncB type="table" tableValues="0 1 1 0"/>
      </feComponentTransfer>
    </filter>
    <filter id="Linear" filterUnits="objectBoundingBox" 
            x="0%" y="0%" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="linear" slope=".5" intercept=".25"/>
        <feFuncG type="linear" slope=".5" intercept="0"/>
        <feFuncB type="linear" slope=".5" intercept=".5"/>
      </feComponentTransfer>
    </filter>
    <filter id="Gamma" filterUnits="objectBoundingBox" 
            x="0%" y="0%" width="100%" height="100%">
      <feComponentTransfer>
        <feFuncR type="gamma" amplitude="2" exponent="5" offset="0"/>
        <feFuncG type="gamma" amplitude="2" exponent="3" offset="0"/>
        <feFuncB type="gamma" amplitude="2" exponent="1" offset="0"/>
      </feComponentTransfer>
    </filter>
  </defs>
  <rect fill="none" stroke="blue"  
        x="1" y="1" width="798" height="398"/>
  <g font-family="Verdana" font-size="75" 
            font-weight="bold" fill="url(#MyGradient)" >
    <rect x="100" y="0" width="600" height="20" />
    <text x="100" y="90">Identity</text>
    <text x="100" y="190" filter="url(#Table)" >TableLookup</text>
    <text x="100" y="290" filter="url(#Linear)" >LinearFunc</text>
    <text x="100" y="390" filter="url(#Gamma)" >GammaFunc</text>
  </g>
</svg>

Example feComponentTransfer

15.12 Filter primitive ‘feComposite’

This filter performs the combination of the two input images pixel-wise in image space using one of the Porter-Duff [PORTERDUFF] compositing operations: over, in, atop, out, xor [SVG-COMPOSITING]. Additionally, a component-wise arithmetic operation (with the result clamped between [0..1]) can be applied.

The arithmetic operation is useful for combining the output from the ‘feDiffuseLighting’ and ‘feSpecularLighting’ filters with texture data. It is also useful for implementing dissolve. If the arithmetic operation is chosen, each result pixel is computed using the following formula:

result = k1*i1*i2 + k2*i1 + k3*i2 + k4

where:

i1 and i2 indicate the corresponding pixel channel values of the input image, which map to in and in2 respectively
k1, k2, k3 and k4 indicate the values of the атрибути with the same name

For this filter primitive, the extent of the resulting image might grow as described in the section that describes the filter primitive subregion.

‘feComposite’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘in2’
‘operator’
‘k1’
‘k2’
‘k3’
‘k4’

DOM Інтерфейсs:

SVGFECompositeElement

Attribute definitions:

operator = "over | in | out | atop | xor | arithmetic": The compositing operation that is to be performed. All of the ‘operator’ types except arithmetic match the corresponding operation as described in [PORTERDUFF]. The arithmetic operator is described above. If атрибут ‘operator’ is not specified, then the effect is as if a value of over were specified.
Animatable: yes.
k1 = "<number>": Only applicable if operator="arithmetic".
If the атрибут is not specified, the effect is as if a value of 0 were specified.
Animatable: yes.
k2 = "<number>": Only applicable if operator="arithmetic".
If the атрибут is not specified, the effect is as if a value of 0 were specified.
Animatable: yes.
k3 = "<number>": Only applicable if operator="arithmetic".
If the атрибут is not specified, the effect is as if a value of 0 were specified.
Animatable: yes.
k4 = "<number>": Only applicable if operator="arithmetic".
If the атрибут is not specified, the effect is as if a value of 0 were specified.
Animatable: yes.
in2 = "(see ‘in’ атрибут)": The second input image to the compositing operation. This атрибут can take on the same values as the ‘in’ атрибут.
Animatable: yes.

Example feComposite shows examples of the six types of feComposite operations. It also shows two different techniques to using the BackgroundImage as part of the compositing operation.

The first two rows render bluish triangles into the background. A filter is applied which composites reddish triangles into the bluish triangles using one of the compositing operations. The result from compositing is drawn onto an opaque white temporary surface, and then that result is written to the canvas. (The opaque white temporary surface obliterates the original bluish triangle.)

The last two rows apply the same compositing operations of reddish triangles into bluish triangles. Якever, the compositing result is directly blended into the canvas (the opaque white temporary surface technique is not used). In some cases, the results are different than when a temporary opaque white surface is used. The original bluish triangle from the background shines through wherever the compositing operation results in completely transparent pixel. In other cases, the result from compositing is blended into the bluish triangle, resulting in a different final color value.

<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
          "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="330" height="195" viewBox="0 0 1100 650" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <title>Example feComposite - Examples of feComposite operations</title>
  <desc>Four rows of six pairs of overlapping triangles depicting
        the six different feComposite operators under different
        opacity values and different clearing of the background.</desc>
	<defs>
    <desc>Define two sets of six filters for each of the six compositing operators.
          The first set wipes out the background image by flooding with opaque white.
          The second set does not wipe out the background, with the result
          that the background sometimes shines through and is other cases
          is blended into itself (i.e., "double-counting").</desc>
    <filter id="overFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feFlood flood-color="#ffffff" flood-opacity="1" result="flood"/>
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="over" result="comp"/>
      <feMerge> <feMergeNode in="flood"/> <feMergeNode in="comp"/> </feMerge>
    </filter>
    <filter id="inFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feFlood flood-color="#ffffff" flood-opacity="1" result="flood"/>
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="in" result="comp"/>
      <feMerge> <feMergeNode in="flood"/> <feMergeNode in="comp"/> </feMerge>
    </filter>
    <filter id="outFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feFlood flood-color="#ffffff" flood-opacity="1" result="flood"/>
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="out" result="comp"/>
      <feMerge> <feMergeNode in="flood"/> <feMergeNode in="comp"/> </feMerge>
    </filter>
    <filter id="atopFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feFlood flood-color="#ffffff" flood-opacity="1" result="flood"/>
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="atop" result="comp"/>
      <feMerge> <feMergeNode in="flood"/> <feMergeNode in="comp"/> </feMerge>
    </filter>
    <filter id="xorFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feFlood flood-color="#ffffff" flood-opacity="1" result="flood"/>
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="xor" result="comp"/>
      <feMerge> <feMergeNode in="flood"/> <feMergeNode in="comp"/> </feMerge>
    </filter>
    <filter id="arithmeticFlood" filterUnits="objectBoundingBox" 
            x="-5%" y="-5%" width="110%" height="110%">
      <feFlood flood-color="#ffffff" flood-opacity="1" result="flood"/>
      <feComposite in="SourceGraphic" in2="BackgroundImage" result="comp"
                   operator="arithmetic" k1=".5" k2=".5" k3=".5" k4=".5"/>
      <feMerge> <feMergeNode in="flood"/> <feMergeNode in="comp"/> </feMerge>
    </filter>
    <filter id="overNoFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="over" result="comp"/>
    </filter>
    <filter id="inNoFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="in" result="comp"/>
    </filter>
    <filter id="outNoFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="out" result="comp"/>
    </filter>
    <filter id="atopNoFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="atop" result="comp"/>
    </filter>
    <filter id="xorNoFlood" filterUnits="objectBoundingBox" x="-5%" y="-5%" width="110%" height="110%">
      <feComposite in="SourceGraphic" in2="BackgroundImage" operator="xor" result="comp"/>
    </filter>
    <filter id="arithmeticNoFlood" filterUnits="objectBoundingBox" 
            x="-5%" y="-5%" width="110%" height="110%">
      <feComposite in="SourceGraphic" in2="BackgroundImage" result="comp"
                   operator="arithmetic" k1=".5" k2=".5" k3=".5" k4=".5"/>
    </filter>
    <path id="Blue100" d="M 0 0 L 100 0 L 100 100 z" fill="#00ffff" />
    <path id="Red100" d="M 0 0 L 0 100 L 100 0 z" fill="#ff00ff" />
    <path id="Blue50" d="M 0 125 L 100 125 L 100 225 z" fill="#00ffff" fill-opacity=".5" />
    <path id="Red50" d="M 0 125 L 0 225 L 100 125 z" fill="#ff00ff" fill-opacity=".5" />
    <g id="TwoBlueTriangles">
      <use xlink:href="#Blue100"/>
      <use xlink:href="#Blue50"/>
    </g>
    <g id="BlueTriangles">
      <use transform="translate(275,25)" xlink:href="#TwoBlueTriangles"/>
      <use transform="translate(400,25)" xlink:href="#TwoBlueTriangles"/>
      <use transform="translate(525,25)" xlink:href="#TwoBlueTriangles"/>
      <use transform="translate(650,25)" xlink:href="#TwoBlueTriangles"/>
      <use transform="translate(775,25)" xlink:href="#TwoBlueTriangles"/>
      <use transform="translate(900,25)" xlink:href="#TwoBlueTriangles"/>
    </g>
  </defs>

  <rect fill="none" stroke="blue" x="1" y="1" width="1098" height="648"/>
  <g font-family="Verdana" font-size="40" shape-rendering="crispEdges">
    <desc>Render the examples using the filters that draw on top of
          an opaque white surface, thus obliterating the background.</desc>
    <g enable-background="new">
      <text x="15" y="75">opacity 1.0</text>
      <text x="15" y="115" font-size="27">(with feFlood)</text>
      <text x="15" y="200">opacity 0.5</text>
      <text x="15" y="240" font-size="27">(with feFlood)</text>
      <use xlink:href="#BlueTriangles"/>
      <g transform="translate(275,25)">
        <use xlink:href="#Red100" filter="url(#overFlood)" />
        <use xlink:href="#Red50" filter="url(#overFlood)" />
        <text x="5" y="275">over</text>
      </g>
      <g transform="translate(400,25)">
        <use xlink:href="#Red100" filter="url(#inFlood)" />
        <use xlink:href="#Red50" filter="url(#inFlood)" />
        <text x="35" y="275">in</text>
      </g>
      <g transform="translate(525,25)">
        <use xlink:href="#Red100" filter="url(#outFlood)" />
        <use xlink:href="#Red50" filter="url(#outFlood)" />
        <text x="15" y="275">out</text>
      </g>
      <g transform="translate(650,25)">
        <use xlink:href="#Red100" filter="url(#atopFlood)" />
        <use xlink:href="#Red50" filter="url(#atopFlood)" />
        <text x="10" y="275">atop</text>
      </g>
      <g transform="translate(775,25)">
        <use xlink:href="#Red100" filter="url(#xorFlood)" />
        <use xlink:href="#Red50" filter="url(#xorFlood)" />
        <text x="15" y="275">xor</text>
      </g>
      <g transform="translate(900,25)">
        <use xlink:href="#Red100" filter="url(#arithmeticFlood)" />
        <use xlink:href="#Red50" filter="url(#arithmeticFlood)" />
        <text x="-25" y="275">arithmetic</text>
      </g>
    </g>
    <g transform="translate(0,325)" enable-background="new">
    <desc>Render the examples using the filters that do not obliterate
          the background, thus sometimes causing the background to continue
          to appear in some cases, and in other cases the background
          image blends into itself ("double-counting").</desc>
      <text x="15" y="75">opacity 1.0</text>
      <text x="15" y="115" font-size="27">(without feFlood)</text>
      <text x="15" y="200">opacity 0.5</text>
      <text x="15" y="240" font-size="27">(without feFlood)</text>
      <use xlink:href="#BlueTriangles"/>
      <g transform="translate(275,25)">
        <use xlink:href="#Red100" filter="url(#overNoFlood)" />
        <use xlink:href="#Red50" filter="url(#overNoFlood)" />
        <text x="5" y="275">over</text>
      </g>
      <g transform="translate(400,25)">
        <use xlink:href="#Red100" filter="url(#inNoFlood)" />
        <use xlink:href="#Red50" filter="url(#inNoFlood)" />
        <text x="35" y="275">in</text>
      </g>
      <g transform="translate(525,25)">
        <use xlink:href="#Red100" filter="url(#outNoFlood)" />
        <use xlink:href="#Red50" filter="url(#outNoFlood)" />
        <text x="15" y="275">out</text>
      </g>
      <g transform="translate(650,25)">
        <use xlink:href="#Red100" filter="url(#atopNoFlood)" />
        <use xlink:href="#Red50" filter="url(#atopNoFlood)" />
        <text x="10" y="275">atop</text>
      </g>
      <g transform="translate(775,25)">
        <use xlink:href="#Red100" filter="url(#xorNoFlood)" />
        <use xlink:href="#Red50" filter="url(#xorNoFlood)" />
        <text x="15" y="275">xor</text>
      </g>
      <g transform="translate(900,25)">
        <use xlink:href="#Red100" filter="url(#arithmeticNoFlood)" />
        <use xlink:href="#Red50" filter="url(#arithmeticNoFlood)" />
        <text x="-25" y="275">arithmetic</text>
      </g>
    </g>
  </g>
</svg>

Example feComposite

15.13 Filter primitive ‘feConvolveMatrix’

feConvolveMatrix applies a matrix convolution filter effect. A convolution combines pixels in the input image with neighboring pixels to produce a resulting image. A wide variety of imaging operations can be achieved through convolutions, including blurring, edge detection, sharpening, embossing and beveling.

A matrix convolution is based on an n-by-m matrix (the convolution kernel) which describes how a given pixel value in the input image is combined with its neighboring pixel values to produce a resulting pixel value. Each result pixel is determined by applying the kernel matrix to the corresponding source pixel and its neighboring pixels. The basic convolution formula which is applied to each color value for a given pixel is:

COLOR_X,Y = (
              SUM _{I=0 to [orderY-1]} {
                SUM _{J=0 to [orderX-1]} {
                  SOURCE _{X-targetX+J, Y-targetY+I} * kernelMatrix_{orderX-J-1,
orderY-I-1}
                }
              }
            ) / divisor + bias * ALPHA_X,Y

where "orderX" and "orderY" represent the X and Y values for the ‘order’ атрибут, "targetX" represents the value of the ‘targetX’ атрибут, "targetY" represents the value of the ‘targetY’ атрибут, "kernelMatrix" represents the value of the ‘kernelMatrix’ атрибут, "divisor" represents the value of the ‘divisor’ атрибут, and "bias" represents the value of the ‘bias’ атрибут.

Note in the above formulas that the values in the kernel matrix are applied such that the kernel matrix is rotated 180 degrees relative to the source and destination images in order to match convolution theory as described in many computer graphics textbooks.

To illustrate, suppose you have a input image which is 5 pixels by 5 pixels, whose color values for one of the color channels are as follows:

    0  20  40 235 235
  100 120 140 235 235
  200 220 240 235 235
  225 225 255 255 255
  225 225 255 255 255

and you define a 3-by-3 convolution kernel as follows:

  1 2 3
  4 5 6
  7 8 9

Let's focus on the color value at the second row and second column of the image (source pixel value is 120). Assuming the simplest case (where the input image's pixel grid aligns perfectly with the kernel's pixel grid) and assuming default values for атрибути ‘divisor’, ‘targetX’ and ‘targetY’, then resulting color value will be:

(9*  0 + 8* 20 + 7* 40 +
6*100 + 5*120 + 4*140 +
3*200 + 2*220 + 1*240) / (9+8+7+6+5+4+3+2+1)

Because they operate on pixels, matrix convolutions are inherently resolution-dependent. To make ‘feConvolveMatrix’ produce resolution-independent results, an explicit value should be provided for either the ‘filterRes’ атрибут on the ‘filter’ елемент and/or атрибут ‘kernelUnitLength’.

‘kernelUnitLength’, in combination with the other атрибути, defines an implicit pixel grid in the filter effects coordinate system (i.e., the coordinate system established by the ‘primitiveUnits’ атрибут). If the pixel grid established by ‘kernelUnitLength’ is not scaled to match the pixel grid established by атрибут ‘filterRes’ (implicitly or explicitly), then the input image will be temporarily rescaled to match its pixels with ‘kernelUnitLength’. The convolution happens on the resampled image. After applying the convolution, the image is resampled back to the original resolution.

When the image must be resampled to match the coordinate system defined by ‘kernelUnitLength’ prior to convolution, or resampled to match the device coordinate system after convolution, it is recommended that high quality viewers make use of appropriate interpolation techniques, for example bilinear or bicubic. Depending on the speed of the available interpolents, this choice may be affected by the ‘image-rendering’ властивість setting. Note that implementations might choose approaches that minimize or eliminate resampling when not necessary to produce proper results, such as when the document is zoomed out such that ‘kernelUnitLength’ is considerably smaller than a device pixel.

‘feConvolveMatrix’

Categories:

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘order’
‘kernelMatrix’
‘divisor’
‘bias’
‘targetX’
‘targetY’
‘edgeMode’
‘kernelUnitLength’
‘preserveAlpha’

DOM Інтерфейсs:

SVGFEConvolveMatrixElement

Attribute definitions:

order = "<number-optional-number>"

Indicates the number of cells in each dimension for ‘kernelMatrix’. The values provided must be <integer>s greater than zero. The first number, <orderX>, indicates the number of columns in the matrix. The second number, <orderY>, indicates the number of rows in the matrix. If <orderY> is not provided, it defaults to <orderX>.
A typical value is order="3". It is recommended that only small values (e.g., 3) be used; higher values may result in very high CPU overhead and usually do not produce results that justify the impact on performance.
If the атрибут is not specified, the effect is as if a value of 3 were specified.
Animatable: yes.

kernelMatrix = "<list of numbers>"

The list of <number>s that make up the kernel matrix for the convolution. Values are separated by space characters and/or a comma. The number of entries in the list must equal <orderX> times <orderY>.
Animatable: yes.

divisor = "<number>"

After applying the ‘kernelMatrix’ to the input image to yield a number, that number is divided by ‘divisor’ to yield the final destination color value. A divisor that is the sum of all the matrix values tends to have an evening effect on the overall color intensity of the result. It is an error to specify a divisor of zero. The default value is the sum of all values in kernelMatrix, with the exception that if the sum is zero, then the divisor is set to 1.
Animatable: yes.

bias = "<number>"

After applying the ‘kernelMatrix’ to the input image to yield a number and applying the ‘divisor’, the ‘bias’ атрибут is added to each component. One application of ‘bias’ is when it is desirable to have .5 gray value be the zero response of the filter. The bias властивість shifts the range of the filter. This allows representation of values that would otherwise be clamped to 0 or 1. If ‘bias’ is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.

targetX = "<integer>"

Determines the positioning in X of the convolution matrix relative to a given target pixel in the input image. The leftmost column of the matrix is column number zero. The value must be such that: 0 <= targetX < orderX. By default, the convolution matrix is centered in X over each pixel of the input image (i.e., targetX = floor ( orderX / 2 )).
Animatable: yes.

targetY = "<integer>"

Determines the positioning in Y of the convolution matrix relative to a given target pixel in the input image. The topmost row of the matrix is row number zero. The value must be such that: 0 <= targetY < orderY. By default, the convolution matrix is centered in Y over each pixel of the input image (i.e., targetY = floor ( orderY / 2 )).
Animatable: yes.

edgeMode = "duplicate | wrap | none"

Determines how to extend the input image as necessary with color values so that the matrix operations can be applied when the kernel is positioned at or near the edge of the input image.

"duplicate" indicates that the input image is extended along each of its borders as necessary by duplicating the color values at the given edge of the input image.

Original N-by-M image, where m=M-1 and n=N-1:
          11 12 ... 1m 1M
          21 22 ... 2m 2M
          .. .. ... .. ..
          n1 n2 ... nm nM
          N1 N2 ... Nm NM
Extended by two pixels using "duplicate":
  11 11   11 12 ... 1m 1M   1M 1M
  11 11   11 12 ... 1m 1M   1M 1M
  11 11   11 12 ... 1m 1M   1M 1M
  21 21   21 22 ... 2m 2M   2M 2M
  .. ..   .. .. ... .. ..   .. ..
  n1 n1   n1 n2 ... nm nM   nM nM
  N1 N1   N1 N2 ... Nm NM   NM NM
  N1 N1   N1 N2 ... Nm NM   NM NM
  N1 N1   N1 N2 ... Nm NM   NM NM

"wrap" indicates that the input image is extended by taking the color values from the opposite edge of the image.

Extended by two pixels using "wrap":
  nm nM   n1 n2 ... nm nM   n1 n2
  Nm NM   N1 N2 ... Nm NM   N1 N2
  1m 1M   11 12 ... 1m 1M   11 12
  2m 2M   21 22 ... 2m 2M   21 22
  .. ..   .. .. ... .. ..   .. ..
  nm nM   n1 n2 ... nm nM   n1 n2
  Nm NM   N1 N2 ... Nm NM   N1 N2
  1m 1M   11 12 ... 1m 1M   11 12
  2m 2M   21 22 ... 2m 2M   21 22

"none" indicates that the input image is extended with pixel values of zero for R, G, B and A.

If атрибут ‘edgeMode’ is not specified, then the effect is as if a value of duplicate were specified.

Animatable: yes.

kernelUnitLength = "<number-optional-number>"

The first number is the <dx> value. The second number is the <dy> value. If the <dy> value is not specified, it defaults to the same value as <dx>. Indicates the intended distance in current filter units (i.e., units as determined by the value of атрибут ‘primitiveUnits’) between successive columns and rows, respectively, in the ‘kernelMatrix’. By specifying value(s) for ‘kernelUnitLength’, the kernel becomes defined in a scalable, abstract coordinate system. If ‘kernelUnitLength’ is not specified, the default value is one pixel in the offscreen bitmap, which is a pixel-based coordinate system, and thus potentially not scalable. For some level of consistency across display media and user agents, it is necessary that a value be provided for at least one of ‘filterRes’ and ‘kernelUnitLength’. In some implementations, the most consistent results and the fastest performance will be achieved if the pixel grid of the temporary offscreen images aligns with the pixel grid of the kernel.
A negative or zero value is an error (see Error processing).
Animatable: yes.

preserveAlpha = "false | true"

A value of false indicates that the convolution will apply to all channels, including the alpha channel. In this case the ALPHA_X,Y of the convolution formula for a given pixel is:

ALPHA_X,Y = (
              SUM _{I=0 to [orderY-1]} {
                SUM _{J=0 to [orderX-1]} {
                  SOURCE _{X-targetX+J, Y-targetY+I} * kernelMatrix_{orderX-J-1,
orderY-I-1}
                }
              }
            ) / divisor + bias

A value of true indicates that the convolution will only apply to the color channels. In this case, the filter will temporarily unpremultiply the color component values, apply the kernel, and then re-premultiply at the end. In this case the ALPHA_X,Y of the convolution formula for a given pixel is:

ALPHA_X,Y = SOURCE_X,Y

If ‘preserveAlpha’ is not specified, then the effect is as if a value of false were specified.
Animatable: yes.

15.14 Filter primitive ‘feDiffuseLighting’

This filter primitive lights an image using the alpha channel as a bump map. The resulting image is an RGBA opaque image based on the light color with alpha = 1.0 everywhere. The lighting calculation follows the standard diffuse component of the Phong lighting модель. The resulting image depends on the light color, light position and surface geometry of the input bump map.

The light map produced by this filter primitive can be combined with a texture image using the multiply term of the arithmetic ‘feComposite’ compositing method. Multiple light sources can be simulated by adding several of these light maps together before applying it to the texture image.

The formulas below make use of 3x3 filters. Because they operate on pixels, such filters are inherently resolution-dependent. To make ‘feDiffuseLighting’ produce resolution-independent results, an explicit value should be provided for either the ‘filterRes’ атрибут on the ‘filter’ елемент and/or атрибут ‘kernelUnitLength’.

‘kernelUnitLength’, in combination with the other атрибути, defines an implicit pixel grid in the filter effects coordinate system (i.e., the coordinate system established by the ‘primitiveUnits’ атрибут). If the pixel grid established by ‘kernelUnitLength’ is not scaled to match the pixel grid established by атрибут ‘filterRes’ (implicitly or explicitly), then the input image will be temporarily rescaled to match its pixels with ‘kernelUnitLength’. The 3x3 filters are applied to the resampled image. After applying the filter, the image is resampled back to its original resolution.

When the image must be resampled, it is recommended that high quality viewers make use of appropriate interpolation techniques, for example bilinear or bicubic. Depending on the speed of the available interpolents, this choice may be affected by the ‘image-rendering’ властивість setting. Note that implementations might choose approaches that minimize or eliminate resampling when not necessary to produce proper results, such as when the document is zoomed out such that ‘kernelUnitLength’ is considerably smaller than a device pixel.

For the formulas that follow, the Norm(A_x,A_y,A_z) function is defined as:

Norm(A_x,A_y,A_z) = sqrt(A_x^2+A_y^2+A_z^2)

The resulting RGBA image is computed as follows:

D_r = k_d * N.L * L_r
D_g = k_d * N.L * L_g
D_b = k_d * N.L * L_b
D_a = 1.0

where

k_d = diffuse lighting constant
N = surface normal unit vector, a function of x and y
L = unit vector pointing from surface to light, a function of x and y in the point and spot light cases
L_r,L_g,L_b = RGB components of light, a function of x and y in the spot light case

N is a function of x and y and depends on the surface gradient as follows:

The surface described by the input alpha image I(x,y) is:

Z (x,y) = surfaceScale * I(x,y)

Surface normal is calculated using the Sobel gradient 3x3 filter. Different filter kernels are used depending on whether the given pixel is on the interior or an edge. For each case, the formula is:

N_x (x,y)= - surfaceScale * FACTOR_x *
           (K_x(0,0)*I(x-dx,y-dy) + K_x(1,0)*I(x,y-dy) + K_x(2,0)*I(x+dx,y-dy) +
            K_x(0,1)*I(x-dx,y)    + K_x(1,1)*I(x,y)    + K_x(2,1)*I(x+dx,y)    +
            K_x(0,2)*I(x-dx,y+dy) + K_x(1,2)*I(x,y+dy) + K_x(2,2)*I(x+dx,y+dy))
N_y (x,y)= - surfaceScale * FACTOR_y *
           (K_y(0,0)*I(x-dx,y-dy) + K_y(1,0)*I(x,y-dy) + K_y(2,0)*I(x+dx,y-dy) +
            K_y(0,1)*I(x-dx,y)    + K_y(1,1)*I(x,y)    + K_y(2,1)*I(x+dx,y)    +
            K_y(0,2)*I(x-dx,y+dy) + K_y(1,2)*I(x,y+dy) + K_y(2,2)*I(x+dx,y+dy))
N_z (x,y) = 1.0

N = (N_x, N_y, N_z) / Norm((N_x,N_y,N_z))

In these formulas, the dx and dy values (e.g., I(x-dx,y-dy)), represent deltas relative to a given (x,y) position for the purpose of estimating the slope of the surface at that point. These deltas are determined by the value (explicit or implicit) of атрибут ‘kernelUnitLength’.

Top/left corner:

FACTOR_x=2/(3*dx)
K_x =
    |  0  0  0 |
    |  0 -2  2 |
    |  0 -1  1 |

FACTOR_y=2/(3*dy)
K_y =
    |  0  0  0 |
    |  0 -2 -1 |
    |  0  2  1 |

Top row:

FACTOR_x=1/(3*dx)
K_x =
    |  0  0  0 |
    | -2  0  2 |
    | -1  0  1 |

FACTOR_y=1/(2*dy)
K_y =
    |  0  0  0 |
    | -1 -2 -1 |
    |  1  2  1 |

Top/right corner:

FACTOR_x=2/(3*dx)
K_x =
    |  0  0  0 |
    | -2  2  0 |
    | -1  1  0 |

FACTOR_y=2/(3*dy)
K_y =
    |  0  0  0 |
    | -1 -2  0 |
    |  1  2  0 |

Left column:

FACTOR_x=1/(2*dx)
K_x =
    | 0 -1  1 |
    | 0 -2  2 |
    | 0 -1  1 |

FACTOR_y=1/(3*dy)
K_y =
    |  0 -2 -1 |
    |  0  0  0 |
    |  0  2  1 |

Interior pixels:

FACTOR_x=1/(4*dx)
K_x =
    | -1  0  1 |
    | -2  0  2 |
    | -1  0  1 |

FACTOR_y=1/(4*dy)
K_y =
    | -1 -2 -1 |
    |  0  0  0 |
    |  1  2  1 |

Right column:

FACTOR_x=1/(2*dx)
K_x =
    | -1  1  0|
    | -2  2  0|
    | -1  1  0|

FACTOR_y=1/(3*dy)
K_y =
    | -1 -2  0 |
    |  0  0  0 |
    |  1  2  0 |

Bottom/left corner:

FACTOR_x=2/(3*dx)
K_x =
    | 0 -1  1 |
    | 0 -2  2 |
    | 0  0  0 |

FACTOR_y=2/(3*dy)
K_y =
    |  0 -2 -1 |
    |  0  2  1 |
    |  0  0  0 |

Bottom row:

FACTOR_x=1/(3*dx)
K_x =
    | -1  0  1 |
    | -2  0  2 |
    |  0  0  0 |

FACTOR_y=1/(2*dy)
K_y =
    | -1 -2 -1 |
    |  1  2  1 |
    |  0  0  0 |

Bottom/right corner:

FACTOR_x=2/(3*dx)
K_x =
    | -1  1  0 |
    | -2  2  0 |
    |  0  0  0 |

FACTOR_y=2/(3*dy)
K_y =
    | -1 -2  0 |
    |  1  2  0 |
    |  0  0  0 |

L, the unit vector from the image sample to the light, is calculated as follows:

For Infinite light sources it is constant:

L_x = cos(azimuth)*cos(elevation)
L_y = sin(azimuth)*cos(elevation)
L_z = sin(elevation)

For Point and spot lights it is a function of position:

L_x = Light_x - x
L_y = Light_y - y
L_z = Light_z - Z(x,y)

L = (L_x, L_y, L_z) / Norm(L_x, L_y, L_z)

where Light_x, Light_y, and Light_z are the input light position.

L_r,L_g,L_b, the light color vector, is a function of position in the spot light case only:

L_r = Light_r*pow((-L.S),specularExponent)
L_g = Light_g*pow((-L.S),specularExponent)
L_b = Light_b*pow((-L.S),specularExponent)

where S is the unit vector pointing from the light to the point (pointsAtX, pointsAtY, pointsAtZ) in the x-y plane:

S_x = pointsAtX - Light_x
S_y = pointsAtY - Light_y
S_z = pointsAtZ - Light_z

S = (S_x, S_y, S_z) / Norm(S_x, S_y, S_z)

If L.S is positive, no light is present. (L_r = L_g = L_b = 0). If ‘limitingConeAngle’ is specified, -L.S < cos(limitingConeAngle) also indicates that no light is present.

‘feDiffuseLighting’

Categories:

Content модель:

Any number of descriptive елементи and exactly one light source елемент, in any order.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘surfaceScale’
‘diffuseConstant’
‘kernelUnitLength’

DOM Інтерфейсs:

SVGFEDiffuseLightingElement

Attribute definitions:

surfaceScale = "<number>": height of surface when A_in = 1.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.
diffuseConstant = "<number>": kd in Phong lighting модель. In SVG, this can be any non-negative number.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.
kernelUnitLength = "<number-optional-number>": The first number is the <dx> value. The second number is the <dy> value. If the <dy> value is not specified, it defaults to the same value as <dx>. Indicates the intended distance in current filter units (i.e., units as determined by the value of атрибут ‘primitiveUnits’) for dx and dy, respectively, in the surface normal calculation formulas. By specifying value(s) for ‘kernelUnitLength’, the kernel becomes defined in a scalable, abstract coordinate system. If ‘kernelUnitLength’ is not specified, the dx and dy values should represent very small deltas relative to a given (x,y) position, which might be implemented in some cases as one pixel in the intermediate image offscreen bitmap, which is a pixel-based coordinate system, and thus potentially not scalable. For some level of consistency across display media and user agents, it is necessary that a value be provided for at least one of ‘filterRes’ and ‘kernelUnitLength’. Discussion of intermediate images are in the Вступ and in the description of атрибут ‘filterRes’.
A negative or zero value is an error (see Error processing).
Animatable: yes.

The light source is defined by one of the child елементи ‘feDistantLight’, ‘fePointLight’ or ‘feSpotLight’. The light color is specified by властивість ‘lighting-color’.

15.15 Filter primitive ‘feDisplacementMap’

This filter primitive uses the pixels values from the image from ‘in2’ to spatially displace the image from ‘in’. This is the transformation to be performed:

P'(x,y) <- P( x + scale * (XC(x,y) - .5), y + scale * (YC(x,y) - .5))

where P(x,y) is the input image, ‘in’, and P'(x,y) is the destination. XC(x,y) and YC(x,y) are the component values of the channel designated by the xChannelSelector and yChannelSelector. For example, to use the R component of ‘in2’ to control displacement in x and the G component of Image2 to control displacement in y, set xChannelSelector to "R" and yChannelSelector to "G".

The displacement map defines the inverse of the mapping performed.

The input image in is to remain premultiplied for this filter primitive. The calculations using the pixel values from ‘in2’ are performed using non-premultiplied color values. If the image from ‘in2’ consists of premultiplied color values, those values are automatically converted into non-premultiplied color values before performing this operation.

This filter can have arbitrary non-localized effect on the input which might require substantial buffering in the processing pipeline. Якever with this formulation, any intermediate buffering needs can be determined by scale which represents the maximum range of displacement in either x or y.

When applying this filter, the source pixel location will often lie between several source pixels. In this case it is recommended that high quality viewers apply an interpolent on the surrounding pixels, for example bilinear or bicubic, rather than simply selecting the nearest source pixel. Depending on the speed of the available interpolents, this choice may be affected by the ‘image-rendering’ властивість setting.

The ‘color-interpolation-filters’ властивість only applies to the ‘in2’ source image and does not apply to the ‘in’ source image. The ‘in’ source image must remain in its current color space.

‘feDisplacementMap’

Categories:

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘in2’
‘scale’
‘xChannelSelector’
‘yChannelSelector’

DOM Інтерфейсs:

SVGFEDisplacementMapElement

Attribute definitions:

scale = "<number>": Displacement scale factor. The amount is expressed in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.
When the value of this атрибут is 0, this operation has no effect on the source image.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
xChannelSelector = "R | G | B | A": Indicates which channel from ‘in2’ to use to displace the pixels in ‘in’ along the x-axis. If атрибут ‘xChannelSelector’ is not specified, then the effect is as if a value of A were specified.
Animatable: yes.
yChannelSelector = "R | G | B | A": Indicates which channel from ‘in2’ to use to displace the pixels in ‘in’ along the y-axis. If атрибут ‘yChannelSelector’ is not specified, then the effect is as if a value of A were specified.
Animatable: yes.
in2 = "(see ‘in’ атрибут)": The second input image, which is used to displace the pixels in the image from атрибут ‘in’. This атрибут can take on the same values as the ‘in’ атрибут.
Animatable: yes.

15.16 Filter primitive ‘feFlood’

This filter primitive creates a rectangle filled with the color and opacity values from властивості ‘flood-color’ and ‘flood-opacity’. The rectangle is as large as the filter primitive subregion established by the ‘x’, ‘y’, ‘width’ and ‘height’ атрибути on the ‘feFlood’ елемент.

‘feFlood’

Categories:

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘animateColor’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’

DOM Інтерфейсs:

SVGFEFloodElement

The ‘flood-color’ властивість indicates what color to use to flood the current filter primitive subregion. The keyword currentColor and ICC colors can be specified in the same manner as within a <paint> specification for the ‘fill’ and ‘stroke’ властивості.

‘flood-color’

Value:	currentColor \| <color> [<icccolor>] \| inherit
Initial:	black
Applies to:	‘feFlood’ елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

The ‘flood-opacity’ властивість defines the opacity value to use across the entire filter primitive subregion.

‘flood-opacity’

Value:	<opacity-value> \| inherit
Initial:	1
Applies to:	‘feFlood’ елементи
Inherited:	no
Percentages:	N/A
Media:	visual
Animatable:	yes

15.17 Filter primitive ‘feGaussianBlur’

This filter primitive performs a Gaussian blur on the input image.

The Gaussian blur kernel is an approximation of the normalized convolution:

G(x,y) = H(x)I(y)

where

H(x) = exp(-x²/ (2s²)) / sqrt(2* pi*s²)

and

I(y) = exp(-y²/ (2t²)) / sqrt(2* pi*t²)

with 's' being the standard deviation in the x direction and 't' being the standard deviation in the y direction, as specified by ‘stdDeviation’.

The value of ‘stdDeviation’ can be either one or two numbers. If two numbers are provided, the first number represents a standard deviation value along the x-axis of the current coordinate system and the second value represents a standard deviation in Y. If one number is provided, then that value is used for both X and Y.

Even if only one value is provided for ‘stdDeviation’, this can be implemented as a separable convolution.

For larger values of 's' (s >= 2.0), an approximation can be used: Three successive box-blurs build a piece-wise quadratic convolution kernel, which approximates the Gaussian kernel to within roughly 3%.

let d = floor(s * 3*sqrt(2*pi)/4 + 0.5)

... if d is odd, use three box-blurs of size 'd', centered on the output pixel.

... if d is even, two box-blurs of size 'd' (the first one centered on the pixel boundary between the output pixel and the one to the left, the second one centered on the pixel boundary between the output pixel and the one to the right) and one box blur of size 'd+1' centered on the output pixel.

Note: the approximation formula also applies correspondingly to 't'.

Frequently this operation will take place on alpha-only images, such as that produced by the built-in input, SourceAlpha. The implementation may notice this and optimize the single channel case. If the input has infinite extent and is constant (e.g FillPaint where the fill is a solid color), this operation has no effect. If the input has infinite extent and the filter result is the input to an ‘feTile’, the filter is evaluated with periodic boundary conditions.

‘feGaussianBlur’

Categories:

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘stdDeviation’

DOM Інтерфейсs:

SVGFEGaussianBlurElement

Attribute definitions:

stdDeviation = "<number-optional-number>": The standard deviation for the blur operation. If two <number>s are provided, the first number represents a standard deviation value along the x-axis of the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент. The second value represents a standard deviation in Y. If one number is provided, then that value is used for both X and Y.
A negative value is an error (see Error processing). A value of zero disables the effect of the given filter primitive (i.e., the result is the filter input image). If ‘stdDeviation’ is 0 in only one of X or Y, then the effect is that the blur is only applied in the direction that has a non-zero value.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.

The example at the start of this chapter makes use of the ‘feGaussianBlur’ filter primitive to create a drop shadow effect.

15.18 Filter primitive ‘feImage’

This filter primitive refers to a graphic external to this filter елемент, which is loaded or rendered into an RGBA raster and becomes the result of the filter primitive.

This filter primitive can refer to an external image or can be a reference to another piece of SVG. It produces an image similar to the built-in image source SourceGraphic except that the graphic comes from an external source.

If the ‘xlink:href’ references a stand-alone image resource such as a JPEG, PNG or SVG file, then the image resource is rendered according to the behavior of the ‘image’ елемент; otherwise, the referenced resource is rendered according to the behavior of the ‘use’ елемент. In either case, the current user coordinate system depends on the value of атрибут ‘primitiveUnits’ on the ‘filter’ елемент. The processing of the ‘preserveAspectRatio’ атрибут on the ‘feImage’ елемент is identical to that of the ‘image’ елемент.

When the referenced image must be resampled to match the device coordinate system, it is recommended that high quality viewers make use of appropriate interpolation techniques, for example bilinear or bicubic. Depending on the speed of the available interpolents, this choice may be affected by the ‘image-rendering’ властивість setting.

‘feImage’

Categories:

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘animateTransform’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘preserveAspectRatio’
‘xlink:href’

DOM Інтерфейсs:

SVGFEImageElement

Attribute definitions:

xlink:href = "<iri>"

An IRI reference to the image source.

Animatable: yes.

preserveAspectRatio = "[defer] <align> [<meetOrSlice>]"

View this example as SVG (SVG-enabled browsers only)

If атрибут ‘preserveAspectRatio’ is not specified, then the effect is as if a value of xMidYMid meet were specified.

Animatable: yes.

Example feImage illustrates how images are placed relative to an object. From left to right:

The default placement of an image. Note that the image is centered in the filter region and has the maximum size that will fit in the region consistent with preserving the aspect ratio.
The image stretched to fit the bounding box of an object.
The image placed using user coordinates. Note that the image is first centered in a box the size of the filter region and has the maximum size that will fit in the box consistent with preserving the aspect ratio. This box is then shifted by the given 'x' and 'y' values relative to the viewport the object is in.

<svg width="600" height="250" viewBox="0 0 600 250"
     xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink">
  <title>Example feImage - Examples of feImage use</title>
  <desc>Three examples of using feImage, the first showing the
        default rendering, the second showing the image fit
        to a box and the third showing the image
        shifted and clipped.</desc>
  <defs>
    <filter id="Default">
      <feImage xlink:href="smiley.png" />
    </filter>
    <filter id="Fitted" primitiveUnits="objectBoundingBox">
      <feImage xlink:href="smiley.png"
	       x="0" y="0" width="100%" height="100%"
	       preserveAspectRatio="none"/>
    </filter>
    <filter id="Shifted">
      <feImage xlink:href="smiley.png"
	       x="500" y="5"/>
    </filter>
  </defs>
  <rect fill="none" stroke="blue"  
        x="1" y="1" width="598" height="248"/>
  <g>
    <rect x="50"  y="25" width="100" height="200" filter="url(#Default)"/>
    <rect x="50"  y="25" width="100" height="200" fill="none" stroke="green"/>
    <rect x="250" y="25" width="100" height="200" filter="url(#Fitted)"/>
    <rect x="250" y="25" width="100" height="200" fill="none" stroke="green"/>
    <rect x="450" y="25" width="100" height="200" filter="url(#Shifted)"/>
    <rect x="450" y="25" width="100" height="200" fill="none" stroke="green"/>
  </g>
</svg>

Example feImage

15.19 Filter primitive ‘feMerge’

This filter primitive composites input image layers on top of each other using the over operator with Input1 (corresponding to the first ‘feMergeNode’ child елемент) on the bottom and the last specified input, InputN (corresponding to the last ‘feMergeNode’ child елемент), on top.

Many effects produce a number of intermediate layers in order to create the final output image. This filter allows us to collapse those into a single image. Although this could be done by using n-1 Composite-filters, it is more convenient to have this common operation available in this form, and offers the implementation some additional flexibility.

Each ‘feMerge’ елемент can have any number of ‘feMergeNode’ subелементи, each of which has an ‘in’ атрибут.

The canonical implementation of feMerge is to render the entire effect into one RGBA layer, and then render the resulting layer on the output device. In certain cases (in particular if the output device itself is a continuous tone device), and since merging is associative, it might be a sufficient approximation to evaluate the effect one layer at a time and render each layer individually onto the output device bottom to top.

If the topmost image input is SourceGraphic and this ‘feMerge’ is the last filter primitive in the filter, the implementation is encouraged to render the layers up to that point, and then render the SourceGraphic directly from its vector description on top.

‘feMerge’

Categories:

Content модель:

Any number of the following елементи, in any order:

‘feMergeNode’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’

DOM Інтерфейсs:

SVGFEMergeElement

‘feMergeNode’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
‘in’

DOM Інтерфейсs:

SVGFEMergeNodeElement

The example at the start of this chapter makes use of the ‘feMerge’ filter primitive to composite two intermediate filter results together.

15.20 Filter primitive ‘feMorphology’

This filter primitive performs "fattening" or "thinning" of artwork. It is particularly useful for fattening or thinning an alpha channel.

The dilation (or erosion) kernel is a rectangle with a width of 2*x-radius and a height of 2*y-radius. In dilation, the output pixel is the individual component-wise maximum of the corresponding R,G,B,A values in the input image's kernel rectangle. In erosion, the output pixel is the individual component-wise minimum of the corresponding R,G,B,A values in the input image's kernel rectangle.

Frequently this operation will take place on alpha-only images, such as that produced by the built-in input, SourceAlpha. In that case, the implementation might want to optimize the single channel case.

If the input has infinite extent and is constant (e.g FillPaint where the fill is a solid color), this operation has no effect. If the input has infinite extent and the filter result is the input to an ‘feTile’, the filter is evaluated with periodic boundary conditions.

Because ‘feMorphology’ operates on premultipied color values, it will always result in color values less than or equal to the alpha channel.

‘feMorphology’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘operator’
‘radius’

DOM Інтерфейсs:

SVGFEMorphologyElement

Attribute definitions:

operator = "erode | dilate": A keyword indicating whether to erode (i.e., thin) or dilate (fatten) the source graphic. If атрибут ‘operator’ is not specified, then the effect is as if a value of erode were specified.
Animatable: yes.
radius = "<number-optional-number>": The radius (or radii) for the operation. If two <number>s are provided, the first number represents a x-radius and the second value represents a y-radius. If one number is provided, then that value is used for both X and Y. The values are in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.
A negative value is an error (see Error processing). A value of zero disables the effect of the given filter primitive (i.e., the result is a transparent black image).
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.

Example feMorphology shows examples of the four types of feMorphology operations.

<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
          "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="5cm" height="7cm" viewBox="0 0 700 500"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example feMorphology - Examples of erode and dilate</title>
  <desc>Five text strings drawn as outlines.
        The first is unfiltered. The second and third use 'erode'.
        The fourth and fifth use 'dilate'.</desc>
  <defs>
    <filter id="Erode3">
      <feMorphology operator="erode" in="SourceGraphic" radius="3" />
    </filter>
    <filter id="Erode6">
      <feMorphology operator="erode" in="SourceGraphic" radius="6" />
    </filter>
    <filter id="Dilate3">
      <feMorphology operator="dilate" in="SourceGraphic" radius="3" />
    </filter>
    <filter id="Dilate6">
      <feMorphology operator="dilate" in="SourceGraphic" radius="6" />
    </filter>
  </defs>
  <rect fill="none" stroke="blue" stroke-width="2"  
        x="1" y="1" width="698" height="498"/>
  <g enable-background="new" >
    <g font-family="Verdana" font-size="75" 
              fill="none" stroke="black" stroke-width="6" >
      <text x="50" y="90">Unfiltered</text>
      <text x="50" y="180" filter="url(#Erode3)" >Erode radius 3</text>
      <text x="50" y="270" filter="url(#Erode6)" >Erode radius 6</text>
      <text x="50" y="360" filter="url(#Dilate3)" >Dilate radius 3</text>
      <text x="50" y="450" filter="url(#Dilate6)" >Dilate radius 6</text>
    </g>
  </g>
</svg>

Example feMorphology

15.21 Filter primitive ‘feOffset’

This filter primitive offsets the input image relative to its current position in the image space by the specified vector.

This is important for effects like drop shadows.

When applying this filter, the destination location may be offset by a fraction of a pixel in device space. In this case a high quality viewer should make use of appropriate interpolation techniques, for example bilinear or bicubic. This is especially recommended for dynamic viewers where this interpolation provides visually smoother movement of images. For static viewers this is less of a concern. Close attention should be made to the ‘image-rendering’ властивість setting to determine the authors intent.

‘feOffset’

Categories:

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘dx’
‘dy’

DOM Інтерфейсs:

SVGFEOffsetElement

Attribute definitions:

dx = "<number>": The amount to offset the input graphic along the x-axis. The offset amount is expressed in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
dy = "<number>": The amount to offset the input graphic along the y-axis. The offset amount is expressed in the coordinate system established by атрибут ‘primitiveUnits’ on the ‘filter’ елемент.
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.

The example at the start of this chapter makes use of the ‘feOffset’ filter primitive to offset the drop shadow from the original source graphic.

15.22 Filter primitive ‘feSpecularLighting’

This filter primitive lights a source graphic using the alpha channel as a bump map. The resulting image is an RGBA image based on the light color. The lighting calculation follows the standard specular component of the Phong lighting модель. The resulting image depends on the light color, light position and surface geometry of the input bump map. The result of the lighting calculation is added. The filter primitive assumes that the viewer is at infinity in the z direction (i.e., the unit vector in the eye direction is (0,0,1) everywhere).

This filter primitive produces an image which contains the specular reflection part of the lighting calculation. Such a map is intended to be combined with a texture using the add term of the arithmetic ‘feComposite’ method. Multiple light sources can be simulated by adding several of these light maps before applying it to the texture image.

The resulting RGBA image is computed as follows:

S_r = k_s * pow(N.H, specularExponent) * L_r S_g = k_s * pow(N.H, specularExponent) * L_g S_b = k_s * pow(N.H, specularExponent) * L_b S_a = max(S_r, S_g, S_b)

where

k_s = specular lighting constant
N = surface normal unit vector, a function of x and y
H = "halfway" unit vector between eye unit vector and light unit vector

L_r,L_g,L_b = RGB components of light

See ‘feDiffuseLighting’ for definition of N and (L_r, L_g, L_b).

The definition of H reflects our assumption of the constant eye vector E = (0,0,1):

H = (L + E) / Norm(L+E)

where L is the light unit vector.

Unlike the ‘feDiffuseLighting’, the ‘feSpecularLighting’ filter produces a non-opaque image. This is due to the fact that the specular result (S_r,S_g,S_b,S_a) is meant to be added to the textured image. The alpha channel of the result is the max of the color components, so that where the specular light is zero, no additional coverage is added to the image and a fully white highlight will add opacity.

The ‘feDiffuseLighting’ and ‘feSpecularLighting’ filters will often be applied together. An implementation may detect this and calculate both maps in one pass, instead of two.

‘feSpecularLighting’

Categories:

Content модель:

Any number of descriptive елементи and exactly one light source елемент, in any order.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’
‘surfaceScale’
‘specularConstant’
‘specularExponent’
‘kernelUnitLength’

DOM Інтерфейсs:

SVGFESpecularLightingElement

Attribute definitions:

surfaceScale = "<number>": height of surface when A_in = 1.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.
specularConstant = "<number>": ks in Phong lighting модель. In SVG, this can be any non-negative number.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.
specularExponent = "<number>": Exponent for specular term, larger is more "shiny". Range 1.0 to 128.0.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.
kernelUnitLength = "<number-optional-number>": The first number is the <dx> value. The second number is the <dy> value. If the <dy> value is not specified, it defaults to the same value as <dx>. Indicates the intended distance in current filter units (i.e., units as determined by the value of атрибут ‘primitiveUnits’) for dx and dy, respectively, in the surface normal calculation formulas. By specifying value(s) for ‘kernelUnitLength’, the kernel becomes defined in a scalable, abstract coordinate system. If ‘kernelUnitLength’ is not specified, the dx and dy values should represent very small deltas relative to a given (x,y) position, which might be implemented in some cases as one pixel in the intermediate image offscreen bitmap, which is a pixel-based coordinate system, and thus potentially not scalable. For some level of consistency across display media and user agents, it is necessary that a value be provided for at least one of ‘filterRes’ and ‘kernelUnitLength’. Discussion of intermediate images are in the Вступ and in the description of атрибут ‘filterRes’.
A negative or zero value is an error (see Error processing).
Animatable: yes.

The light source is defined by one of the child елементи ‘feDistantLight’, ‘fePointLight’ or ‘feDistantLight’. The light color is specified by властивість ‘lighting-color’.

The example at the start of this chapter makes use of the ‘feSpecularLighting’ filter primitive to achieve a highly reflective, 3D glowing effect.

15.23 Filter primitive ‘feTile’

This filter primitive fills a target rectangle with a repeated, tiled pattern of an input image. The target rectangle is as large as the filter primitive subregion established by the ‘x’, ‘y’, ‘width’ and ‘height’ атрибути on the ‘feTile’ елемент.

Typically, the input image has been defined with its own filter primitive subregion in order to define a reference tile. ‘feTile’ replicates the reference tile in both X and Y to completely fill the target rectangle. The top/left corner of each given tile is at location (x+i*width,y+j*height), where (x,y) represents the top/left of the input image's filter primitive subregion, width and height represent the width and height of the input image's filter primitive subregion, and i and j can be any integer value. In most cases, the input image will have a smaller filter primitive subregion than the ‘feTile’ in order to achieve a repeated pattern effect.

Implementers must take appropriate measures in constructing the tiled image to avoid artifacts between tiles, particularly in situations where the user to device transform includes shear and/or rotation. Unless care is taken, interpolation can lead to edge pixels in the tile having opacity values lower or higher than expected due to the interaction of painting adjacent tiles which each have partial overlap with particular pixels.

‘feTile’

Categories:

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘in’

DOM Інтерфейсs:

SVGFETileElement

15.24 Filter primitive ‘feTurbulence’

This filter primitive creates an image using the Perlin turbulence function. It allows the synthesis of artificial textures like clouds or marble. For a detailed description the of the Perlin turbulence function, see "Texturing and Modeling", Ebert et al, AP Professional, 1994. The resulting image will fill the entire filter primitive subregion for this filter primitive.

It is possible to create bandwidth-limited noise by synthesizing only one octave.

The C code below shows the exact algorithm used for this filter effect.

For fractalSum, you get a turbFunctionResult that is aimed at a range of -1 to 1 (the actual result might exceed this range in some cases). To convert to a color value, use the formula colorValue = ((turbFunctionResult * 255) + 255) / 2, then clamp to the range 0 to 255.

For turbulence, you get a turbFunctionResult that is aimed at a range of 0 to 1 (the actual result might exceed this range in some cases). To convert to a color value, use the formula colorValue = (turbFunctionResult * 255), then clamp to the range 0 to 255.

The following order is used for applying the pseudo random numbers. An initial seed value is computed based on атрибут ‘seed’. Then the implementation computes the lattice points for R, then continues getting additional pseudo random numbers relative to the last generated pseudo random number and computes the lattice points for G, and so on for B and A.

The generated color and alpha values are in the color space determined by the value of властивість ‘color-interpolation-filters’:

/* Produces results in the range [1, 2**31 - 2].
Algorithm is: r = (a * r) mod m
where a = 16807 and m = 2**31 - 1 = 2147483647
See [Park & Miller], CACM vol. 31 no. 10 p. 1195, Oct. 1988
To test: the algorithm should produce the result 1043618065
as the 10,000th generated number if the original seed is 1.
*/
#define RAND_m 2147483647 /* 2**31 - 1 */
#define RAND_a 16807 /* 7**5; primitive root of m */
#define RAND_q 127773 /* m / a */
#define RAND_r 2836 /* m % a */
long setup_seed(long lSeed)
{
  if (lSeed <= 0) lSeed = -(lSeed % (RAND_m - 1)) + 1;
  if (lSeed > RAND_m - 1) lSeed = RAND_m - 1;
  return lSeed;
}
long random(long lSeed)
{
  long result;
  result = RAND_a * (lSeed % RAND_q) - RAND_r * (lSeed / RAND_q);
  if (result <= 0) result += RAND_m;
  return result;
}
#define BSize 0x100
#define BM 0xff
#define PerlinN 0x1000
#define NP 12 /* 2^PerlinN */
#define NM 0xfff
static uLatticeSelector[BSize + BSize + 2];
static double fGradient[4][BSize + BSize + 2][2];
struct StitchInfo
{
  int nWidth; // Як much to subtract to wrap for stitching.
  int nHeight;
  int nWrapX; // Minimum value to wrap.
  int nWrapY;
};
static void init(long lSeed)
{
  double s;
  int i, j, k;
  lSeed = setup_seed(lSeed);
  for(k = 0; k < 4; k++)
  {
    for(i = 0; i < BSize; i++)
    {
      uLatticeSelector[i] = i;
      for (j = 0; j < 2; j++)
        fGradient[k][i][j] = (double)(((lSeed = random(lSeed)) % (BSize + BSize)) - BSize) / BSize;
      s = double(sqrt(fGradient[k][i][0] * fGradient[k][i][0] + fGradient[k][i][1] * fGradient[k][i][1]));
      fGradient[k][i][0] /= s;
      fGradient[k][i][1] /= s;
    }
  }
  while(--i)
  {
    k = uLatticeSelector[i];
    uLatticeSelector[i] = uLatticeSelector[j = (lSeed = random(lSeed)) % BSize];
    uLatticeSelector[j] = k;
  }
  for(i = 0; i < BSize + 2; i++)
  {
    uLatticeSelector[BSize + i] = uLatticeSelector[i];
    for(k = 0; k < 4; k++)
      for(j = 0; j < 2; j++)
        fGradient[k][BSize + i][j] = fGradient[k][i][j];
  }
}
#define s_curve(t) ( t * t * (3. - 2. * t) )
#define lerp(t, a, b) ( a + t * (b - a) )
double noise2(int nColorChannel, double vec[2], StitchInfo *pStitchInfo)
{
  int bx0, bx1, by0, by1, b00, b10, b01, b11;
  double rx0, rx1, ry0, ry1, *q, sx, sy, a, b, t, u, v;
  register i, j;
  t = vec[0] + PerlinN;
  bx0 = (int)t;
  bx1 = bx0+1;
  rx0 = t - (int)t;
  rx1 = rx0 - 1.0f;
  t = vec[1] + PerlinN;
  by0 = (int)t;
  by1 = by0+1;
  ry0 = t - (int)t;
  ry1 = ry0 - 1.0f;
  // If stitching, adjust lattice points accordingly.
  if(pStitchInfo != NULL)
  {
    if(bx0 >= pStitchInfo->nWrapX)
      bx0 -= pStitchInfo->nWidth;
    if(bx1 >= pStitchInfo->nWrapX)
      bx1 -= pStitchInfo->nWidth;
    if(by0 >= pStitchInfo->nWrapY)
      by0 -= pStitchInfo->nHeight;
    if(by1 >= pStitchInfo->nWrapY)
      by1 -= pStitchInfo->nHeight;
  }
  bx0 &= BM;
  bx1 &= BM;
  by0 &= BM;
  by1 &= BM;
  i = uLatticeSelector[bx0];
  j = uLatticeSelector[bx1];
  b00 = uLatticeSelector[i + by0];
  b10 = uLatticeSelector[j + by0];
  b01 = uLatticeSelector[i + by1];
  b11 = uLatticeSelector[j + by1];
  sx = double(s_curve(rx0));
  sy = double(s_curve(ry0));
  q = fGradient[nColorChannel][b00]; u = rx0 * q[0] + ry0 * q[1];
  q = fGradient[nColorChannel][b10]; v = rx1 * q[0] + ry0 * q[1];
  a = lerp(sx, u, v);
  q = fGradient[nColorChannel][b01]; u = rx0 * q[0] + ry1 * q[1];
  q = fGradient[nColorChannel][b11]; v = rx1 * q[0] + ry1 * q[1];
  b = lerp(sx, u, v);
  return lerp(sy, a, b);
}
double turbulence(int nColorChannel, double *point, double fBaseFreqX, double fBaseFreqY,
          int nNumOctaves, bool bFractalSum, bool bDoStitching,
          double fTileX, double fTileY, double fTileWidth, double fTileHeight)
{
  StitchInfo stitch;
  StitchInfo *pStitchInfo = NULL; // Not stitching when NULL.
  // Adjust the base frequencies if necessary for stitching.
  if(bDoStitching)
  {
    // When stitching tiled turbulence, the frequencies must be adjusted
    // so that the tile borders will be continuous.
    if(fBaseFreqX != 0.0)
    {
      double fLoFreq = double(floor(fTileWidth * fBaseFreqX)) / fTileWidth;
      double fHiFreq = double(ceil(fTileWidth * fBaseFreqX)) / fTileWidth;
      if(fBaseFreqX / fLoFreq < fHiFreq / fBaseFreqX)
        fBaseFreqX = fLoFreq;
      else
        fBaseFreqX = fHiFreq;
    }
    if(fBaseFreqY != 0.0)
    {
      double fLoFreq = double(floor(fTileHeight * fBaseFreqY)) / fTileHeight;
      double fHiFreq = double(ceil(fTileHeight * fBaseFreqY)) / fTileHeight;
      if(fBaseFreqY / fLoFreq < fHiFreq / fBaseFreqY)
        fBaseFreqY = fLoFreq;
      else
        fBaseFreqY = fHiFreq;
    }
    // Set up initial stitch values.
    pStitchInfo = &stitch;
    stitch.nWidth = int(fTileWidth * fBaseFreqX + 0.5f);
    stitch.nWrapX = fTileX * fBaseFreqX + PerlinN + stitch.nWidth;
    stitch.nHeight = int(fTileHeight * fBaseFreqY + 0.5f);
    stitch.nWrapY = fTileY * fBaseFreqY + PerlinN + stitch.nHeight;
  }
  double fSum = 0.0f;
  double vec[2];
  vec[0] = point[0] * fBaseFreqX;
  vec[1] = point[1] * fBaseFreqY;
  double ratio = 1;
  for(int nOctave = 0; nOctave < nNumOctaves; nOctave++)
  {
    if(bFractalSum)
      fSum += double(noise2(nColorChannel, vec, pStitchInfo) / ratio);
    else
      fSum += double(fabs(noise2(nColorChannel, vec, pStitchInfo)) / ratio);
    vec[0] *= 2;
    vec[1] *= 2;
    ratio *= 2;
    if(pStitchInfo != NULL)
    {
      // Update stitch values. Subtracting PerlinN before the multiplication and
      // adding it afterward simplifies to subtracting it once.
      stitch.nWidth *= 2;
      stitch.nWrapX = 2 * stitch.nWrapX - PerlinN;
      stitch.nHeight *= 2;
      stitch.nWrapY = 2 * stitch.nWrapY - PerlinN;
    }
  }
  return fSum;
}

‘feTurbulence’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

‘animate’
‘set’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
filter primitive атрибути — ‘x’, ‘y’, ‘width’, ‘height’, ‘result’
‘class’
‘style’
‘baseFrequency’
‘numOctaves’
‘seed’
‘stitchTiles’
‘type’

DOM Інтерфейсs:

SVGFETurbulenceElement

Attribute definitions:

baseFrequency = "<number-optional-number>": The base frequency (frequencies) parameter(s) for the noise function. If two <number>s are provided, the first number represents a base frequency in the X direction and the second value represents a base frequency in the Y direction. If one number is provided, then that value is used for both X and Y.
A negative value for base frequency is an error (see Error processing).
If the атрибут is not specified, then the effect is as if a value of 0 were specified.
Animatable: yes.
numOctaves = "<integer>": The numOctaves parameter for the noise function.
If the атрибут is not specified, then the effect is as if a value of 1 were specified.
Animatable: yes.
seed = "<number>": The starting number for the pseudo random number generator.
If the атрибут is not specified, then the effect is as if a value of 0 were specified. When the seed number is handed over to the algorithm above it must first be truncated, i.e. rounded to the closest integer value towards zero.
Animatable: yes.
stitchTiles = "stitch | noStitch": If stitchTiles="noStitch", no attempt it made to achieve smooth transitions at the border of tiles which contain a turbulence function. Sometimes the result will show clear discontinuities at the tile borders.
If stitchTiles="stitch", then the user agent will automatically adjust baseFrequency-x and baseFrequency-y values such that the feTurbulence node's width and height (i.e., the width and height of the current subregion) contains an integral number of the Perlin tile width and height for the first octave. The baseFrequency will be adjusted up or down depending on which way has the smallest relative (not absolute) change as follows: Given the frequency, calculate lowFreq=floor(width*frequency)/width and hiFreq=ceil(width*frequency)/width. If frequency/lowFreq < hiFreq/frequency then use lowFreq, else use hiFreq. While generating turbulence values, generate lattice vectors as normal for Perlin Noise, except for those lattice points that lie on the right or bottom edges of the active area (the size of the resulting tile). In those cases, copy the lattice vector from the opposite edge of the active area.
If атрибут ‘stitchTiles’ is not specified, then the effect is as if a value of noStitch were specified.

Animatable: yes.
type = "fractalNoise | turbulence": Indicates whether the filter primitive should perform a noise or turbulence function. If атрибут ‘type’ is not specified, then the effect is as if a value of turbulence were specified.
Animatable: yes.

Example feTurbulence shows the effects of various parameter settings for feTurbulence.

<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
          "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="450px" height="325px" viewBox="0 0 450 325"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <title>Example feTurbulence - Examples of feTurbulence operations</title>
  <desc>Six rectangular areas showing the effects of 
        various parameter settings for feTurbulence.</desc>
  <g  font-family="Verdana" text-anchor="middle" font-size="10" >
    <defs>
      <filter id="Turb1" filterUnits="objectBoundingBox" 
              x="0%" y="0%" width="100%" height="100%">
        <feTurbulence type="turbulence" baseFrequency="0.05" numOctaves="2"/>
      </filter>
      <filter id="Turb2" filterUnits="objectBoundingBox" 
              x="0%" y="0%" width="100%" height="100%">
        <feTurbulence type="turbulence" baseFrequency="0.1" numOctaves="2"/>
      </filter>
      <filter id="Turb3" filterUnits="objectBoundingBox" 
              x="0%" y="0%" width="100%" height="100%">
        <feTurbulence type="turbulence" baseFrequency="0.05" numOctaves="8"/>
      </filter>
      <filter id="Turb4" filterUnits="objectBoundingBox" 
              x="0%" y="0%" width="100%" height="100%">
        <feTurbulence type="fractalNoise" baseFrequency="0.1" numOctaves="4"/>
      </filter>
      <filter id="Turb5" filterUnits="objectBoundingBox" 
              x="0%" y="0%" width="100%" height="100%">
        <feTurbulence type="fractalNoise" baseFrequency="0.4" numOctaves="4"/>
      </filter>
      <filter id="Turb6" filterUnits="objectBoundingBox" 
              x="0%" y="0%" width="100%" height="100%">
        <feTurbulence type="fractalNoise" baseFrequency="0.1" numOctaves="1"/>
      </filter>
    </defs>

    <rect x="1" y="1" width="448" height="323"
          fill="none" stroke="blue" stroke-width="1"  />

    <rect x="25" y="25" width="100" height="75" filter="url(#Turb1)"  />
    <text x="75" y="117">type=turbulence</text>
    <text x="75" y="129">baseFrequency=0.05</text>
    <text x="75" y="141">numOctaves=2</text>

    <rect x="175" y="25" width="100" height="75" filter="url(#Turb2)"  />
    <text x="225" y="117">type=turbulence</text>
    <text x="225" y="129">baseFrequency=0.1</text>
    <text x="225" y="141">numOctaves=2</text>

    <rect x="325" y="25" width="100" height="75" filter="url(#Turb3)"  />
    <text x="375" y="117">type=turbulence</text>
    <text x="375" y="129">baseFrequency=0.05</text>
    <text x="375" y="141">numOctaves=8</text>

    <rect x="25" y="180" width="100" height="75" filter="url(#Turb4)"  />
    <text x="75" y="272">type=fractalNoise</text>
    <text x="75" y="284">baseFrequency=0.1</text>
    <text x="75" y="296">numOctaves=4</text>

    <rect x="175" y="180" width="100" height="75" filter="url(#Turb5)"  />
    <text x="225" y="272">type=fractalNoise</text>
    <text x="225" y="284">baseFrequency=0.4</text>
    <text x="225" y="296">numOctaves=4</text>

    <rect x="325" y="180" width="100" height="75" filter="url(#Turb6)"  />
    <text x="375" y="272">type=fractalNoise</text>
    <text x="375" y="284">baseFrequency=0.1</text>
    <text x="375" y="296">numOctaves=1</text>
  </g>
</svg>

Example feTurbulence

15.25 DOM interfaces

15.25.1 Інтерфейс SVGFilterElement

The SVGFilterElement interface corresponds to the ‘filter’ елемент.

interface SVGFilterElement : SVGElement,
                             SVGURIReference,
                             SVGLangSpace,
                             SVGExternalResourcesRequired,
                             SVGStylable,
                             SVGUnitTypes {

  readonly атрибут SVGAnimatedEnumeration filterUnits;
  readonly атрибут SVGAnimatedEnumeration primitiveUnits;
  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
  readonly атрибут SVGAnimatedLength width;
  readonly атрибут SVGAnimatedLength height;
  readonly атрибут SVGAnimatedInteger filterResX;
  readonly атрибут SVGAnimatedInteger filterResY;

  void setFilterRes(in unsigned long filterResX, in unsigned long filterResY) raises(DOMException);
};

Attributes:

filterUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘filterUnits’ on the given ‘filter’ елемент. Takes one of the constants defined in SVGUnitTypes.
primitiveUnits (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘primitiveUnits’ on the given ‘filter’ елемент. Takes one of the constants defined in SVGUnitTypes.
x (readonly SVGAnimatedLength): Corresponds to атрибут ‘x’ on the given ‘filter’ елемент.
y (readonly SVGAnimatedLength): Corresponds to атрибут ‘y’ on the given ‘filter’ елемент.
width (readonly SVGAnimatedLength): Corresponds to атрибут ‘width’ on the given ‘filter’ елемент.
height (readonly SVGAnimatedLength): Corresponds to атрибут ‘height’ on the given ‘filter’ елемент.
filterResX (readonly SVGAnimatedInteger): Corresponds to атрибут ‘filterRes’ on the given ‘filter’ елемент. Contains the X component of атрибут ‘filterRes’.
filterResY (readonly SVGAnimatedInteger): Corresponds to атрибут ‘filterRes’ on the given ‘filter’ елемент. Contains the Y component (possibly computed automatically) of атрибут ‘filterRes’.

Operations:

void setFilterRes(in unsigned long filterResX, in unsigned long filterResY)

Sets the values for атрибут ‘filterRes’.

Parameters

unsigned long filterResX

The X component of атрибут ‘filterRes’.
unsigned long filterResY

The Y component of атрибут ‘filterRes’.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

15.25.2 Інтерфейс SVGFilterPrimitiveStandardAttributes

This interface defines the set of DOM атрибути that are common across the filter primitive interfaces.

interface SVGFilterPrimitiveStandardAttributes : SVGStylable {
  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
  readonly атрибут SVGAnimatedLength width;
  readonly атрибут SVGAnimatedLength height;
  readonly атрибут SVGAnimatedString result;
};

Attributes:

x (readonly SVGAnimatedLength): Corresponds to атрибут ‘x’ on the given елемент.
y (readonly SVGAnimatedLength): Corresponds to атрибут ‘y’ on the given елемент.
width (readonly SVGAnimatedLength): Corresponds to атрибут ‘width’ on the given елемент.
height (readonly SVGAnimatedLength): Corresponds to атрибут ‘height’ on the given елемент.
result (readonly SVGAnimatedString): Corresponds to атрибут ‘result’ on the given елемент.

15.25.3 Інтерфейс SVGFEBlendElement

The SVGFEBlendElement interface corresponds to the ‘feBlend’ елемент.

interface SVGFEBlendElement : SVGElement,
                              SVGFilterPrimitiveStandardAttributes {

  // Blend Mode Types
  const unsigned short SVG_FEBLEND_MODE_UNKNOWN = 0;
  const unsigned short SVG_FEBLEND_MODE_NORMAL = 1;
  const unsigned short SVG_FEBLEND_MODE_MULTIPLY = 2;
  const unsigned short SVG_FEBLEND_MODE_SCREEN = 3;
  const unsigned short SVG_FEBLEND_MODE_DARKEN = 4;
  const unsigned short SVG_FEBLEND_MODE_LIGHTEN = 5;

  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedString in2;
  readonly атрибут SVGAnimatedEnumeration mode;
};

Constants in group “Blend Mode Types”:

SVG_FEBLEND_MODE_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_FEBLEND_MODE_NORMAL (unsigned short): Corresponds to value 'normal'.
SVG_FEBLEND_MODE_MULTIPLY (unsigned short): Corresponds to value 'multiply'.
SVG_FEBLEND_MODE_SCREEN (unsigned short): Corresponds to value 'screen'.
SVG_FEBLEND_MODE_DARKEN (unsigned short): Corresponds to value 'darken'.
SVG_FEBLEND_MODE_LIGHTEN (unsigned short): Corresponds to value 'lighten'.

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feBlend’ елемент.
in2 (readonly SVGAnimatedString): Corresponds to атрибут ‘in2’ on the given ‘feBlend’ елемент.
mode (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘mode’ on the given ‘feBlend’ елемент. Takes one of the SVG_FEBLEND_MODE_* constants defined on this interface.

15.25.4 Інтерфейс SVGFEColorMatrixElement

The SVGFEColorMatrixElement interface corresponds to the ‘feColorMatrix’ елемент.

interface SVGFEColorMatrixElement : SVGElement,
                                    SVGFilterPrimitiveStandardAttributes {

  // Color Matrix Types
  const unsigned short SVG_FECOLORMATRIX_TYPE_UNKNOWN = 0;
  const unsigned short SVG_FECOLORMATRIX_TYPE_MATRIX = 1;
  const unsigned short SVG_FECOLORMATRIX_TYPE_SATURATE = 2;
  const unsigned short SVG_FECOLORMATRIX_TYPE_HUEROTATE = 3;
  const unsigned short SVG_FECOLORMATRIX_TYPE_LUMINANCETOALPHA = 4;

  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedEnumeration type;
  readonly атрибут SVGAnimatedNumberList values;
};

Constants in group “Color Matrix Types”:

SVG_FECOLORMATRIX_TYPE_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_FECOLORMATRIX_TYPE_MATRIX (unsigned short): Corresponds to value 'matrix'.
SVG_FECOLORMATRIX_TYPE_SATURATE (unsigned short): Corresponds to value 'saturate'.
SVG_FECOLORMATRIX_TYPE_HUEROTATE (unsigned short): Corresponds to value 'hueRotate'.
SVG_FECOLORMATRIX_TYPE_LUMINANCETOALPHA (unsigned short): Corresponds to value 'luminanceToAlpha'.

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feColorMatrix’ елемент.
type (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘type’ on the given ‘feColorMatrix’ елемент. Takes one of the SVG_FECOLORMATRIX_TYPE_* constants defined on this interface.
values (readonly SVGAnimatedNumberList): Corresponds to атрибут ‘values’ on the given ‘feColorMatrix’ елемент.

15.25.5 Інтерфейс SVGFEComponentTransferElement

The SVGFEComponentTransferElement interface corresponds to the ‘feComponentTransfer’ елемент.

interface SVGFEComponentTransferElement : SVGElement,
                                          SVGFilterPrimitiveStandardAttributes {
  readonly атрибут SVGAnimatedString in1;
};

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feComponentTransfer’ елемент.

15.25.6 Інтерфейс SVGComponentTransferFunctionElement

This interface defines a base interface used by the component transfer function interfaces.

interface SVGComponentTransferFunctionElement : SVGElement {

  // Component Transfer Types
  const unsigned short SVG_FECOMPONENTTRANSFER_TYPE_UNKNOWN = 0;
  const unsigned short SVG_FECOMPONENTTRANSFER_TYPE_IDENTITY = 1;
  const unsigned short SVG_FECOMPONENTTRANSFER_TYPE_TABLE = 2;
  const unsigned short SVG_FECOMPONENTTRANSFER_TYPE_DISCRETE = 3;
  const unsigned short SVG_FECOMPONENTTRANSFER_TYPE_LINEAR = 4;
  const unsigned short SVG_FECOMPONENTTRANSFER_TYPE_GAMMA = 5;

  readonly атрибут SVGAnimatedEnumeration type;
  readonly атрибут SVGAnimatedNumberList tableValues;
  readonly атрибут SVGAnimatedNumber slope;
  readonly атрибут SVGAnimatedNumber intercept;
  readonly атрибут SVGAnimatedNumber amplitude;
  readonly атрибут SVGAnimatedNumber exponent;
  readonly атрибут SVGAnimatedNumber offset;
};

Constants in group “Component Transfer Types”:

SVG_FECOMPONENTTRANSFER_TYPE_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_FECOMPONENTTRANSFER_TYPE_IDENTITY (unsigned short): Corresponds to value 'identity'.
SVG_FECOMPONENTTRANSFER_TYPE_TABLE (unsigned short): Corresponds to value 'table'.
SVG_FECOMPONENTTRANSFER_TYPE_DISCRETE (unsigned short): Corresponds to value 'discrete'.
SVG_FECOMPONENTTRANSFER_TYPE_LINEAR (unsigned short): Corresponds to value 'linear'.
SVG_FECOMPONENTTRANSFER_TYPE_GAMMA (unsigned short): Corresponds to value 'gamma'.

Attributes:

type (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘type’ on the given елемент. Takes one of the SVG_FECOMPONENTTRANSFER_TYPE_* constants defined on this interface.
tableValues (readonly SVGAnimatedNumberList): Corresponds to атрибут ‘tableValues’ on the given елемент.
slope (readonly SVGAnimatedNumber): Corresponds to атрибут ‘slope’ on the given елемент.
intercept (readonly SVGAnimatedNumber): Corresponds to атрибут ‘intercept’ on the given елемент.
amplitude (readonly SVGAnimatedNumber): Corresponds to атрибут ‘amplitude’ on the given елемент.
exponent (readonly SVGAnimatedNumber): Corresponds to атрибут ‘exponent’ on the given елемент.
offset (readonly SVGAnimatedNumber): Corresponds to атрибут ‘offset’ on the given елемент.

15.25.7 Інтерфейс SVGFEFuncRElement

The SVGFEFuncRElement interface corresponds to the ‘feFuncR’ елемент.

interface SVGFEFuncRElement : SVGComponentTransferFunctionElement {
};

15.25.8 Інтерфейс SVGFEFuncGElement

The SVGFEFuncRElement interface corresponds to the ‘feFuncG’ елемент.

interface SVGFEFuncGElement : SVGComponentTransferFunctionElement {
};

15.25.9 Інтерфейс SVGFEFuncBElement

The SVGFEFuncBElement interface corresponds to the ‘feFuncB’ елемент.

interface SVGFEFuncBElement : SVGComponentTransferFunctionElement {
};

15.25.10 Інтерфейс SVGFEFuncAElement

The SVGFEFuncAElement interface corresponds to the ‘feFuncA’ елемент.

interface SVGFEFuncAElement : SVGComponentTransferFunctionElement {
};

15.25.11 Інтерфейс SVGFECompositeElement

The SVGFECompositeElement interface corresponds to the ‘feComposite’ елемент.

interface SVGFECompositeElement : SVGElement,
                                  SVGFilterPrimitiveStandardAttributes {

  // Composite Operators
  const unsigned short SVG_FECOMPOSITE_OPERATOR_UNKNOWN = 0;
  const unsigned short SVG_FECOMPOSITE_OPERATOR_OVER = 1;
  const unsigned short SVG_FECOMPOSITE_OPERATOR_IN = 2;
  const unsigned short SVG_FECOMPOSITE_OPERATOR_OUT = 3;
  const unsigned short SVG_FECOMPOSITE_OPERATOR_ATOP = 4;
  const unsigned short SVG_FECOMPOSITE_OPERATOR_XOR = 5;
  const unsigned short SVG_FECOMPOSITE_OPERATOR_ARITHMETIC = 6;

  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedString in2;
  readonly атрибут SVGAnimatedEnumeration operator;
  readonly атрибут SVGAnimatedNumber k1;
  readonly атрибут SVGAnimatedNumber k2;
  readonly атрибут SVGAnimatedNumber k3;
  readonly атрибут SVGAnimatedNumber k4;
};

Constants in group “Composite Operators”:

SVG_FECOMPOSITE_OPERATOR_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_FECOMPOSITE_OPERATOR_OVER (unsigned short): Corresponds to value 'over'.
SVG_FECOMPOSITE_OPERATOR_IN (unsigned short): Corresponds to value 'in'.
SVG_FECOMPOSITE_OPERATOR_OUT (unsigned short): Corresponds to value 'out'.
SVG_FECOMPOSITE_OPERATOR_ATOP (unsigned short): Corresponds to value 'atop'.
SVG_FECOMPOSITE_OPERATOR_XOR (unsigned short): Corresponds to value 'xor'.
SVG_FECOMPOSITE_OPERATOR_ARITHMETIC (unsigned short): Corresponds to value 'arithmetic'.

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feComposite’ елемент.
in2 (readonly SVGAnimatedString): Corresponds to атрибут ‘in2’ on the given ‘feComposite’ елемент.
operator (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘operator’ on the given ‘feComposite’ елемент. Takes one of the SVG_FECOMPOSITE_OPERATOR_* constants defined on this interface.
k1 (readonly SVGAnimatedNumber): Corresponds to атрибут ‘k1’ on the given ‘feComposite’ елемент.
k2 (readonly SVGAnimatedNumber): Corresponds to атрибут ‘k2’ on the given ‘feComposite’ елемент.
k3 (readonly SVGAnimatedNumber): Corresponds to атрибут ‘k3’ on the given ‘feComposite’ елемент.
k4 (readonly SVGAnimatedNumber): Corresponds to атрибут ‘k4’ on the given ‘feComposite’ елемент.

15.25.12 Інтерфейс SVGFEConvolveMatrixElement

The SVGFEConvolveMatrixElement interface corresponds to the ‘feConvolveMatrix’ елемент.

interface SVGFEConvolveMatrixElement : SVGElement,
                                       SVGFilterPrimitiveStandardAttributes {

  // Edge Mode Values
  const unsigned short SVG_EDGEMODE_UNKNOWN = 0;
  const unsigned short SVG_EDGEMODE_DUPLICATE = 1;
  const unsigned short SVG_EDGEMODE_WRAP = 2;
  const unsigned short SVG_EDGEMODE_NONE = 3;

  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedInteger orderX;
  readonly атрибут SVGAnimatedInteger orderY;
  readonly атрибут SVGAnimatedNumberList kernelMatrix;
  readonly атрибут SVGAnimatedNumber divisor;
  readonly атрибут SVGAnimatedNumber bias;
  readonly атрибут SVGAnimatedInteger targetX;
  readonly атрибут SVGAnimatedInteger targetY;
  readonly атрибут SVGAnimatedEnumeration edgeMode;
  readonly атрибут SVGAnimatedNumber kernelUnitLengthX;
  readonly атрибут SVGAnimatedNumber kernelUnitLengthY;
  readonly атрибут SVGAnimatedBoolean preserveAlpha;
};

Constants in group “Edge Mode Values”:

SVG_EDGEMODE_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_EDGEMODE_DUPLICATE (unsigned short): Corresponds to value 'duplicate'.
SVG_EDGEMODE_WRAP (unsigned short): Corresponds to value 'wrap'.
SVG_EDGEMODE_NONE (unsigned short): Corresponds to value 'none'.

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feConvolveMatrix’ елемент.
orderX (readonly SVGAnimatedInteger): Corresponds to атрибут ‘order’ on the given ‘feConvolveMatrix’ елемент.
orderY (readonly SVGAnimatedInteger): Corresponds to атрибут ‘order’ on the given ‘feConvolveMatrix’ елемент.
kernelMatrix (readonly SVGAnimatedNumberList): Corresponds to атрибут ‘kernelMatrix’ on the given ‘feConvolveMatrix’ елемент.
divisor (readonly SVGAnimatedNumber): Corresponds to атрибут ‘divisor’ on the given ‘feConvolveMatrix’ елемент.
bias (readonly SVGAnimatedNumber): Corresponds to атрибут ‘bias’ on the given ‘feConvolveMatrix’ елемент.
targetX (readonly SVGAnimatedInteger): Corresponds to атрибут ‘targetX’ on the given ‘feConvolveMatrix’ елемент.
targetY (readonly SVGAnimatedInteger): Corresponds to атрибут ‘targetY’ on the given ‘feConvolveMatrix’ елемент.
edgeMode (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘edgeMode’ on the given ‘feConvolveMatrix’ елемент. Takes one of the SVG_EDGEMODE_* constants defined on this interface.
kernelUnitLengthX (readonly SVGAnimatedNumber): Corresponds to атрибут ‘kernelUnitLength’ on the given ‘feConvolveMatrix’ елемент.
kernelUnitLengthY (readonly SVGAnimatedNumber): Corresponds to атрибут ‘kernelUnitLength’ on the given ‘feConvolveMatrix’ елемент.
preserveAlpha (readonly SVGAnimatedBoolean): Corresponds to атрибут ‘preserveAlpha’ on the given ‘feConvolveMatrix’ елемент.

15.25.13 Інтерфейс SVGFEDiffuseLightingElement

The SVGFEDiffuseLightingElement interface corresponds to the ‘feDiffuseLighting’ елемент.

interface SVGFEDiffuseLightingElement : SVGElement,
                                        SVGFilterPrimitiveStandardAttributes {
  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedNumber surfaceScale;
  readonly атрибут SVGAnimatedNumber diffuseConstant;
  readonly атрибут SVGAnimatedNumber kernelUnitLengthX;
  readonly атрибут SVGAnimatedNumber kernelUnitLengthY;
};

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feDiffuseLighting’ елемент.
surfaceScale (readonly SVGAnimatedNumber): Corresponds to атрибут ‘surfaceScale’ on the given ‘feDiffuseLighting’ елемент.
diffuseConstant (readonly SVGAnimatedNumber): Corresponds to атрибут ‘diffuseConstant’ on the given ‘feDiffuseLighting’ елемент.
kernelUnitLengthX (readonly SVGAnimatedNumber): Corresponds to атрибут ‘kernelUnitLength’ on the given ‘feDiffuseLighting’ елемент.
kernelUnitLengthY (readonly SVGAnimatedNumber): Corresponds to атрибут ‘kernelUnitLength’ on the given ‘feDiffuseLighting’ елемент.

15.25.14 Інтерфейс SVGFEDistantLightElement

The SVGFEDistantLightElement interface corresponds to the ‘feDistantLight’ елемент.

interface SVGFEDistantLightElement : SVGElement {
  readonly атрибут SVGAnimatedNumber azimuth;
  readonly атрибут SVGAnimatedNumber elevation;
};

Attributes:

azimuth (readonly SVGAnimatedNumber): Corresponds to атрибут ‘azimuth’ on the given ‘feDistantLight’ елемент.
elevation (readonly SVGAnimatedNumber): Corresponds to атрибут ‘elevation’ on the given ‘feDistantLight’ елемент.

15.25.15 Інтерфейс SVGFEPointLightElement

The SVGFEPointLightElement interface corresponds to the ‘fePointLight’ елемент.

interface SVGFEPointLightElement : SVGElement {
  readonly атрибут SVGAnimatedNumber x;
  readonly атрибут SVGAnimatedNumber y;
  readonly атрибут SVGAnimatedNumber z;
};

Attributes:

x (readonly SVGAnimatedNumber): Corresponds to атрибут ‘x’ on the given ‘fePointLight’ елемент.
y (readonly SVGAnimatedNumber): Corresponds to атрибут ‘y’ on the given ‘fePointLight’ елемент.
z (readonly SVGAnimatedNumber): Corresponds to атрибут ‘z’ on the given ‘fePointLight’ елемент.

15.25.16 Інтерфейс SVGFESpotLightElement

The SVGFESpotLightElement interface corresponds to the ‘feSpotLight’ елемент.

interface SVGFESpotLightElement : SVGElement {
  readonly атрибут SVGAnimatedNumber x;
  readonly атрибут SVGAnimatedNumber y;
  readonly атрибут SVGAnimatedNumber z;
  readonly атрибут SVGAnimatedNumber pointsAtX;
  readonly атрибут SVGAnimatedNumber pointsAtY;
  readonly атрибут SVGAnimatedNumber pointsAtZ;
  readonly атрибут SVGAnimatedNumber specularExponent;
  readonly атрибут SVGAnimatedNumber limitingConeAngle;
};

Attributes:

x (readonly SVGAnimatedNumber): Corresponds to атрибут ‘x’ on the given ‘feSpotLight’ елемент.
y (readonly SVGAnimatedNumber): Corresponds to атрибут ‘y’ on the given ‘feSpotLight’ елемент.
z (readonly SVGAnimatedNumber): Corresponds to атрибут ‘z’ on the given ‘feSpotLight’ елемент.
pointsAtX (readonly SVGAnimatedNumber): Corresponds to атрибут ‘pointsAtX’ on the given ‘feSpotLight’ елемент.
pointsAtY (readonly SVGAnimatedNumber): Corresponds to атрибут ‘pointsAtY’ on the given ‘feSpotLight’ елемент.
pointsAtZ (readonly SVGAnimatedNumber): Corresponds to атрибут ‘pointsAtZ’ on the given ‘feSpotLight’ елемент.
specularExponent (readonly SVGAnimatedNumber): Corresponds to атрибут ‘specularExponent’ on the given ‘feSpotLight’ елемент.
limitingConeAngle (readonly SVGAnimatedNumber): Corresponds to атрибут ‘limitingConeAngle’ on the given ‘feSpotLight’ елемент.

15.25.17 Інтерфейс SVGFEDisplacementMapElement

The SVGFEDisplacementMapElement interface corresponds to the ‘feDisplacementMap’ елемент.

interface SVGFEDisplacementMapElement : SVGElement,
                                        SVGFilterPrimitiveStandardAttributes {

  // Channel Selectors
  const unsigned short SVG_CHANNEL_UNKNOWN = 0;
  const unsigned short SVG_CHANNEL_R = 1;
  const unsigned short SVG_CHANNEL_G = 2;
  const unsigned short SVG_CHANNEL_B = 3;
  const unsigned short SVG_CHANNEL_A = 4;

  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedString in2;
  readonly атрибут SVGAnimatedNumber scale;
  readonly атрибут SVGAnimatedEnumeration xChannelSelector;
  readonly атрибут SVGAnimatedEnumeration yChannelSelector;
};

Constants in group “Channel Selectors”:

SVG_CHANNEL_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_CHANNEL_R (unsigned short): Corresponds to value 'R'.
SVG_CHANNEL_G (unsigned short): Corresponds to value 'G'.
SVG_CHANNEL_B (unsigned short): Corresponds to value 'B'.
SVG_CHANNEL_A (unsigned short): Corresponds to value 'A'.

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feDisplacementMap’ елемент.
in2 (readonly SVGAnimatedString): Corresponds to атрибут ‘in2’ on the given ‘feDisplacementMap’ елемент.
scale (readonly SVGAnimatedNumber): Corresponds to атрибут ‘scale’ on the given ‘feDisplacementMap’ елемент.
xChannelSelector (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘xChannelSelector’ on the given ‘feDisplacementMap’ елемент. Takes one of the SVG_CHANNEL_* constants defined on this interface.
yChannelSelector (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘yChannelSelector’ on the given ‘feDisplacementMap’ елемент. Takes one of the SVG_CHANNEL_* constants defined on this interface.

15.25.18 Інтерфейс SVGFEFloodElement

The SVGFEFloodElement interface corresponds to the ‘feFlood’ елемент.

interface SVGFEFloodElement : SVGElement,
                              SVGFilterPrimitiveStandardAttributes {
};

15.25.19 Інтерфейс SVGFEGaussianBlurElement

The SVGFEGaussianBlurElement interface corresponds to the ‘feGaussianBlur’ елемент.

interface SVGFEGaussianBlurElement : SVGElement,
                                     SVGFilterPrimitiveStandardAttributes {

  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedNumber stdDeviationX;
  readonly атрибут SVGAnimatedNumber stdDeviationY;

  void setStdDeviation(in float stdDeviationX, in float stdDeviationY) raises(DOMException);
};

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feGaussianBlur’ елемент.
stdDeviationX (readonly SVGAnimatedNumber): Corresponds to атрибут ‘stdDeviation’ on the given ‘feGaussianBlur’ елемент. Contains the X component of атрибут ‘stdDeviation’.
stdDeviationY (readonly SVGAnimatedNumber): Corresponds to атрибут ‘stdDeviation’ on the given ‘feGaussianBlur’ елемент. Contains the Y component (possibly computed automatically) of атрибут ‘stdDeviation’.

Operations:

void setStdDeviation(in float stdDeviationX, in float stdDeviationY)

Sets the values for атрибут ‘stdDeviation’.

Parameters

float stdDeviationX

The X component of атрибут ‘stdDeviation’.
float stdDeviationY

The Y component of атрибут ‘stdDeviation’.

Exceptions

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

15.25.20 Інтерфейс SVGFEImageElement

The SVGFEImageElement interface corresponds to the ‘feImage’ елемент.

interface SVGFEImageElement : SVGElement,
                              SVGURIReference,
                              SVGLangSpace,
                              SVGExternalResourcesRequired,
                              SVGFilterPrimitiveStandardAttributes {
  readonly атрибут SVGAnimatedPreserveAspectRatio preserveAspectRatio;
};

Attributes:

preserveAspectRatio (readonly SVGAnimatedPreserveAspectRatio): Corresponds to атрибут ‘preserveAspectRatio’ on the given ‘feImage’ елемент.

15.25.21 Інтерфейс SVGFEMergeElement

The SVGFEMergeElement interface corresponds to the ‘feMerge’ елемент.

interface SVGFEMergeElement : SVGElement,
                              SVGFilterPrimitiveStandardAttributes {
};

15.25.22 Інтерфейс SVGFEMergeNodeElement

The SVGFEMergeNodeElement interface corresponds to the ‘feMergeNode’ елемент.

interface SVGFEMergeNodeElement : SVGElement {
  readonly атрибут SVGAnimatedString in1;
};

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feMergeNode’ елемент.

15.25.23 Інтерфейс SVGFEMorphologyElement

The SVGFEMorphologyElement interface corresponds to the ‘feMorphology’ елемент.

interface SVGFEMorphologyElement : SVGElement,
                                   SVGFilterPrimitiveStandardAttributes {

  // Morphology Operators
  const unsigned short SVG_MORPHOLOGY_OPERATOR_UNKNOWN = 0;
  const unsigned short SVG_MORPHOLOGY_OPERATOR_ERODE = 1;
  const unsigned short SVG_MORPHOLOGY_OPERATOR_DILATE = 2;

  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedEnumeration operator;
  readonly атрибут SVGAnimatedNumber radiusX;
  readonly атрибут SVGAnimatedNumber radiusY;
};

Constants in group “Morphology Operators”:

SVG_MORPHOLOGY_OPERATOR_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_MORPHOLOGY_OPERATOR_ERODE (unsigned short): Corresponds to value 'erode'.
SVG_MORPHOLOGY_OPERATOR_DILATE (unsigned short): Corresponds to value 'dilate'.

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feMorphology’ елемент.
operator (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘operator’ on the given ‘feMorphology’ елемент. Takes one of the SVG_MORPHOLOGY_OPERATOR_* constants defined on this interface.
radiusX (readonly SVGAnimatedNumber): Corresponds to атрибут ‘radius’ on the given ‘feMorphology’ елемент.
radiusY (readonly SVGAnimatedNumber): Corresponds to атрибут ‘radius’ on the given ‘feMorphology’ елемент.

15.25.24 Інтерфейс SVGFEOffsetElement

The SVGFEOffsetElement interface corresponds to the ‘feOffset’ елемент.

interface SVGFEOffsetElement : SVGElement,
                               SVGFilterPrimitiveStandardAttributes {
  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedNumber dx;
  readonly атрибут SVGAnimatedNumber dy;
};

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feOffset’ елемент.
dx (readonly SVGAnimatedNumber): Corresponds to атрибут ‘dx’ on the given ‘feOffset’ елемент.
dy (readonly SVGAnimatedNumber): Corresponds to атрибут ‘dy’ on the given ‘feOffset’ елемент.

15.25.25 Інтерфейс SVGFESpecularLightingElement

The SVGFESpecularLightingElement interface corresponds to the ‘feSpecularLighting’ елемент.

interface SVGFESpecularLightingElement : SVGElement,
                                         SVGFilterPrimitiveStandardAttributes {
  readonly атрибут SVGAnimatedString in1;
  readonly атрибут SVGAnimatedNumber surfaceScale;
  readonly атрибут SVGAnimatedNumber specularConstant;
  readonly атрибут SVGAnimatedNumber specularExponent;
  readonly атрибут SVGAnimatedNumber kernelUnitLengthX;
  readonly атрибут SVGAnimatedNumber kernelUnitLengthY;
};

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feSpecularLighting’ елемент.
surfaceScale (readonly SVGAnimatedNumber): Corresponds to атрибут ‘surfaceScale’ on the given ‘feSpecularLighting’ елемент.
specularConstant (readonly SVGAnimatedNumber): Corresponds to атрибут ‘specularConstant’ on the given ‘feSpecularLighting’ елемент.
specularExponent (readonly SVGAnimatedNumber): Corresponds to атрибут ‘specularExponent’ on the given ‘feSpecularLighting’ елемент.
kernelUnitLengthX (readonly SVGAnimatedNumber): Corresponds to атрибут ‘kernelUnitLength’ on the given ‘feSpecularLighting’ елемент.
kernelUnitLengthY (readonly SVGAnimatedNumber): Corresponds to атрибут ‘kernelUnitLength’ on the given ‘feSpecularLighting’ елемент.

15.25.26 Інтерфейс SVGFETileElement

The SVGFETileElement interface corresponds to the ‘feTile’ елемент.

interface SVGFETileElement : SVGElement,
                             SVGFilterPrimitiveStandardAttributes {
  readonly атрибут SVGAnimatedString in1;
};

Attributes:

in1 (readonly SVGAnimatedString): Corresponds to атрибут ‘in’ on the given ‘feTile’ елемент.

15.25.27 Інтерфейс SVGFETurbulenceElement

The SVGFETurbulenceElement interface corresponds to the ‘feTurbulence’ елемент.

interface SVGFETurbulenceElement : SVGElement,
                                   SVGFilterPrimitiveStandardAttributes {

  // Turbulence Types
  const unsigned short SVG_TURBULENCE_TYPE_UNKNOWN = 0;
  const unsigned short SVG_TURBULENCE_TYPE_FRACTALNOISE = 1;
  const unsigned short SVG_TURBULENCE_TYPE_TURBULENCE = 2;

  // Stitch Опції
  const unsigned short SVG_STITCHTYPE_UNKNOWN = 0;
  const unsigned short SVG_STITCHTYPE_STITCH = 1;
  const unsigned short SVG_STITCHTYPE_NOSTITCH = 2;

  readonly атрибут SVGAnimatedNumber baseFrequencyX;
  readonly атрибут SVGAnimatedNumber baseFrequencyY;
  readonly атрибут SVGAnimatedInteger numOctaves;
  readonly атрибут SVGAnimatedNumber seed;
  readonly атрибут SVGAnimatedEnumeration stitchTiles;
  readonly атрибут SVGAnimatedEnumeration type;
};

Constants in group “Turbulence Types”:

SVG_TURBULENCE_TYPE_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_TURBULENCE_TYPE_FRACTALNOISE (unsigned short): Corresponds to value 'fractalNoise'.
SVG_TURBULENCE_TYPE_TURBULENCE (unsigned short): Corresponds to value 'turbulence'.

Constants in group “Stitch Опції”:

SVG_STITCHTYPE_UNKNOWN (unsigned short): The type is not one of predefined types. It is invalid to attempt to define a new value of this type or to attempt to switch an existing value to this type.
SVG_STITCHTYPE_STITCH (unsigned short): Corresponds to value 'stitch'.
SVG_STITCHTYPE_NOSTITCH (unsigned short): Corresponds to value 'noStitch'.

Attributes:

baseFrequencyX (readonly SVGAnimatedNumber): Corresponds to атрибут ‘baseFrequency’ on the given ‘feTurbulence’ елемент. Contains the X component of the ‘baseFrequency’ атрибут.
baseFrequencyY (readonly SVGAnimatedNumber): Corresponds to атрибут ‘baseFrequency’ on the given ‘feTurbulence’ елемент. Contains the Y component of the (possibly computed automatically) ‘baseFrequency’ атрибут.
numOctaves (readonly SVGAnimatedInteger): Corresponds to атрибут ‘numOctaves’ on the given ‘feTurbulence’ елемент.
seed (readonly SVGAnimatedNumber): Corresponds to атрибут ‘seed’ on the given ‘feTurbulence’ елемент.
stitchTiles (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘stitchTiles’ on the given ‘feTurbulence’ елемент. Takes one of the SVG_STITCHTYPE_* constants defined on this interface.
type (readonly SVGAnimatedEnumeration): Corresponds to атрибут ‘type’ on the given ‘feTurbulence’ елемент. Takes one of the SVG_TURBULENCE_TYPE_* constants defined on this interface.

16 Interactivity

16.1 Вступ
16.2 Complete list of supported events
16.3 User interface events
16.4 Pointer events
16.5 Hit-testing and processing order for user interface events
- 16.5.1 Hit-testing
- 16.5.2 Event processing
16.6 The ‘pointer-events’ властивість
16.7 Magnification and panning
16.8 Cursors
16.9 DOM interfaces
- 16.9.1 Інтерфейс SVGCursorElement

16.1 Вступ

SVG content can be interactive (i.e., responsive to user-initiated events) by utilizing the following features in the SVG language:

User-initiated actions such as button presses on the pointing device (e.g., a mouse) can cause animations or scripts to execute.
The user can initiate hyperlinks to new Web pages (see Links out of SVG content: the ‘a’ елемент) by actions such as mouse clicks when the pointing device is positioned over particular graphics елементи.
In many cases, depending on the value of the ‘zoomAndPan’ атрибут on the ‘svg’ елемент and on the characteristics of the user agent, users are able to zoom into and pan around SVG content.
User movements of the pointing device can cause changes to the cursor that shows the current position of the pointing device.

This chapter describes:

information about events, including under which circumstances events are triggered
how to indicate whether a given document can be zoomed and panned
how to specify which cursors to use

Related information can be found in other chapters:

hyperlinks are discussed in Links
scripting and event атрибути are discussed in Scripting
SVG's relationship to DOM2 events is discussed in Relationship with DOM2 event модель
animation is discussed in Animation

16.2 Complete list of supported events

The following aspects of SVG are affected by events:

Using SVG Document Object Model (DOM), a script can register DOM 2 event listeners ([DOM2EVENTS], section 1.3) so that script can be invoked when a given event occurs.
SVG includes event атрибути on selected елементи which define script that can be executed when a given event occurs in association with the given елемент.
SVG's animation елементи can be defined to begin or end based on events.

The following table lists all of the events which are recognized and supported in SVG. The Event name in the first column is the name to use within SVG's animation елементи to define the events which can start or end animations. The DOM2 name in the second column is the name to use when defining DOM 2 event listeners ([DOM2EVENTS], section 1.3). The Event атрибут name in the fourth column contains the corresponding name of the event атрибути that can be attached to елементи in the SVG language.

Requirements in the table on whether an event of a given type bubbles or is cancelable apply only to events that are created and dispatched by the user agent. Events of those types created from script using the createEvent method on the DocumentEvent interface can be made to bubble or be cancelable with the initEvent method.

Event name and description	DOM2 name	DOM2 category	Event атрибут name
focusin Occurs when an елемент receives focus, such as when a ‘text’ becomes selected.	DOMFocusIn	UIEvent	onfocusin
focusout Occurs when an елемент loses focus, such as when a ‘text’ becomes unselected.	DOMFocusOut	UIEvent	onfocusout
activate Occurs when an елемент is activated, for instance, through a mouse click or a keypress. A numerical argument is provided to give an indication of the type of activation that occurs: 1 for a simple activation (e.g. a simple click or Enter), 2 for hyperactivation (for instance a double click or Shift Enter).	DOMActivate	UIEvent	onactivate
click Occurs when the pointing device button is clicked over an елемент. A click is defined as a mousedown and mouseup over the same screen location. The sequence of these events is: `mousedown`, `mouseup`, `click`. If multiple clicks occur at the same screen location, the sequence repeats with the `detail` атрибут incrementing with each repetition.	(same)	MouseEvent	onclick
mousedown Occurs when the pointing device button is pressed over an елемент.	(same)	MouseEvent	onmousedown
mouseup Occurs when the pointing device button is released over an елемент.	(same)	MouseEvent	onmouseup
mouseover Occurs when the pointing device is moved onto an елемент.	(same)	MouseEvent	onmouseover
mousemove Occurs when the pointing device is moved while it is over an елемент.	(same)	MouseEvent	onmousemove
mouseout Occurs when the pointing device is moved away from an елемент.	(same)	MouseEvent	onmouseout
DOMSubtreeModified This is a general event for notification of all changes to the document. It can be used instead of the more specific events listed below. (The normative definition of this event is the description in the DOM2 specification.)	(same)	MutationEvent	none
DOMNodeInserted Fired when a node has been added as a child of another node. (The normative definition of this event is the description in the DOM2 specification.)	(same)	MutationEvent	none
DOMNodeRemoved Fired when a node is being removed from another node. (The normative definition of this event is the description in the DOM2 specification.)	(same)	MutationEvent	none
DOMNodeRemovedFromDocument Fired when a node is being removed from a document, either through direct removal of the Node or removal of a subtree in which it is contained. (The normative definition of this event is the description in the DOM2 specification.)	(same)	MutationEvent	none
DOMNodeInsertedIntoDocument Fired when a node is being inserted into a document, either through direct insertion of the Node or insertion of a subtree in which it is contained. (The normative definition of this event is the description in the DOM2 specification.)	(same)	MutationEvent	none
DOMAttrModified Fired after an атрибут has been modified on a node. (The normative definition of this event is the description in the DOM2 specification.)	(same)	MutationEvent	none
DOMCharacterDataModified Fired after CharacterData within a node has been modified but the node itself has not been inserted or deleted. (The normative definition of this event is the description in the DOM2 specification.)	(same)	MutationEvent	none
SVGLoad The event is triggered at the point at which the user agent has fully parsed the елемент and its descendants and is ready to act appropriately upon that елемент, such as being ready to render the елемент to the target device. Referenced external resources that are required must be loaded, parsed and ready to render before the event is triggered. Optional external resources are not required to be ready for the event to be triggered. SVGLoad events do not bubble and are not cancelable.	(same)	none	onload
SVGUnload Only applicable to outermost svg елементи. The unload event occurs when the DOM implementation removes a document from a window or frame. SVGUnload events do not bubble and are not cancelable.	(same)	none	onunload
SVGAbort The abort event occurs when page loading is stopped before an елемент has been allowed to load completely. SVGAbort events bubble but are not cancelable.	(same)	none	onabort
SVGError The error event occurs when an елемент does not load properly or when an error occurs during script execution. SVGError events bubble but are not cancelable.	(same)	none	onerror
SVGResize Occurs when a document view is being resized. This event is only applicable to outermost svg елементи and is dispatched after the resize operation has taken place. The target of the event is the ‘svg’ елемент. SVGResize events bubble but are not cancelable.	(same)	none	onresize
SVGScroll Occurs when a document view is being shifted along the X or Y or both axis, either through a direct user interaction or any change on the currentTranslate властивість available on SVGSVGElement interface. This event is only applicable to outermost svg елементи and is dispatched after the shift modification has taken place. The target of the event is the ‘svg’ елемент. SVGScroll events bubble but are not cancelable.	(same)	none	onscroll
SVGZoom Occurs when the zoom level of a document view is being changed, either through a direct user interaction or any change to the currentScale властивість available on SVGSVGElement interface. This event is only applicable to outermost svg елементи and is dispatched after the zoom level modification has taken place. The target of the event is the ‘svg’ елемент. SVGZoom events bubble but are not cancelable.	none	none	onzoom
beginEvent Occurs when an animation елемент begins. For details, see the description of Інтерфейс TimeEvent in the SMIL Animation specification.	none	none	onbegin
endEvent Occurs when an animation елемент ends. For details, see the description of Інтерфейс TimeEvent in the SMIL Animation specification.	none	none	onend
repeatEvent Occurs when an animation елемент repeats. It is raised each time the елемент repeats, after the first iteration. For details, see the description of Інтерфейс TimeEvent in the SMIL Animation specification.	none	none	onrepeat

As in DOM 2 Key events ([DOM2EVENTS], section 1.6.3), the SVG specification does not provide a key event set. An event set designed for use with keyboard input devices will be included in a later version of the DOM and SVG specifications.

Details on the parameters passed to event listeners for the event types from DOM2 can be found in the DOM2 specification. For other event types, the parameters passed to event listeners are described elsewhere in this specification.

Event listener атрибути can be specified on some елементи to listen to a given event. The script in such атрибути is run only in response to "bubbling" and "at target" phase events dispatched to the елемент.

Likewise, event-value timing specifiers used in animation елемент ‘begin’ and ‘end’ атрибути are resolved to concrete times only in response to "bubbling" and "at target" phase events dispatched to the relevant елемент.

16.3 User interface events

On user agents which support interactivity, it is common for authors to define SVG documents such that they are responsive to user interface events. Among the set of possible user events are pointer events, keyboard events, and document events.

In response to user interface (UI) events, the author might start an animation, perform a hyperlink to another Web page, highlight part of the document (e.g., change the color of the graphics елементи which are under the pointer), initiate a "roll-over" (e.g., cause some previously hidden graphics елементи to appear near the pointer) or launch a script which communicates with a remote database.

16.4 Pointer events

User interface events that occur because of user actions performed on a pointer device are called pointer events.

Many systems support pointer devices such as a mouse or trackball. On systems which use a mouse, pointer events consist of actions such as mouse movements and mouse clicks. On systems with a different pointer device, the pointing device often emulates the behavior of the mouse by providing a mechanism for equivalent user actions, such as a button to press which is equivalent to a mouse click.

For each pointer event, the SVG user agent determines the target елемент of a given pointer event. The target елемент is the topmost graphics елемент whose relevant graphical content is under the pointer at the time of the event. (See властивість ‘pointer-events’ for a description of how to determine whether an елемент's relevant graphical content is under the pointer, and thus in which circumstances that graphic елемент can be the target елемент for a pointer event.) When an елемент is not displayed (i.e., when the ‘display’ властивість on that елемент or one of its ancestors has a value of none), that елемент cannot be the target of pointer events.

If a target елемент for the pointer event exists, then the event is dispatched to that елемент according to the normal event flow ([DOM2EVENTS], section 1.2). Note, however, that if the target елемент is in a ‘use’ елемент shadow tree, that the event flow will include SVGElementInstance objects. See The ‘use’ елемент for details.

If a target елемент for the pointer event does not exist, then the event is ignored.

16.5 Hit-testing and processing order for user interface events

There are two distinct aspects of pointer-device interaction with an елемент or area:

hit-testing, to determine if a pointer event (such as a mouse movement or mouse click) occurred within the interaction area of an елемент, and the subsequent DOM event flow;
functional processing of actions associated with any relevant елемент.

16.5.1 Hit-testing

Determining whether a pointer event results in a positive hit-test depends upon the position of the pointer, the size and shape of the graphics елемент, and the computed value of the ‘pointer-events’ властивість on the елемент. The definition of the ‘pointer-events’ властивість below describes the exact region that is sensitive to pointer events for a given type of graphics елемент.

Note that the ‘svg’ елемент is not a graphics елемент, and in a Conforming SVG Stand-Alone File a rootmost ‘svg’ елемент will never be the target of pointer events, though events can bubble to this елемент. If a pointer event does not result in a positive hit-test on a graphics елемент, then it should evoke any user-agent-specific window behavior, such as a presenting a context menu or controls to allow zooming and panning of an SVG document fragment.

This specification does not define the behavior of pointer events on the rootmost ‘svg’ елемент for SVG images which are embedded by reference or inclusion within another document, e.g., whether the rootmost ‘svg’ елемент embedded in an HTML document intercepts mouse click events; future specifications may define this behavior, but for the purpose of this specification, the behavior is implementation-specific.

16.5.2 Event processing

An елемент which is the target of a user interface event may have particular interaction behaviors, depending upon the type of елемент and whether it has explicit associated interactions, such as scripted event listeners, CSS pseudo-classes matches, or declarative animations with event-based timing. The algorithm and order for processing user interface events for a given target елемент, after dispatching the DOM event, is as follows:

If an event handler registered on this елемент invokes the preventDefault() DOM method, then no further processing for this елемент is performed, and the event follows the event flow processing as described in DOM Level 2 Events [DOM2EVENTS] (or its successor);
If the елемент has an associated title or description, such as a ‘title’ елемент or an ‘xlink:title’ атрибут, and the user agent supports the display of such information (e.g. via a tooltip or status-bar message), that information should be displayed, as appropriate to the type of pointer event;
If the елемент matches any relevant dynamic pseudo-class selectors appropriate to the type of pointer event, such as :hover, :active, or :focus as described in [CSS2], section 5.11, then the relevant class властивості are applied;
If the елемент and the event type are associated with the activation or cancelation of declarative animation though the use of event-value timing specifiers, any corresponding instance times must be resolved, and any conseqential actions of this instance time resolution (such as immediately starting or stopping the animation) must be performed;
If the елемент is a hyperlink (e.g., it is a descendant елемент of an ‘a’ елемент), and the pointer event is of a type that activates that hyperlink (e.g. via a mouse click), and if the hyperlink traversal changes the context of the content (e.g. opens a different document, or moves the pointer away from this елемент by moving to another part of the same document), then no further processing for this елемент is performed;
If the елемент is a text content елемент, and the event type is one which the user agent recognizes as part of a text-selection operation (e.g., a mouse click and drag, or a double-click), then the text selection algorithm is performed;
If the event type is one which the user agent associates with the evocation of special user-interface controls (e.g., a right-click or command-click evoking a context menu), the user agent should evoke such user-agent-specific behavior, such as presenting a context menu or controls to allow zooming and panning of an SVG document fragment.

16.6 The ‘pointer-events’ властивість

In different circumstances, authors may want to control under what conditions particular graphic елементи can become the target of pointer events. For example, the author might want a given елемент to receive pointer events only when the pointer is over the stroked perimeter of a given shape. In other cases, the author might want a given елемент to ignore pointer events under all circumstances so that graphical елементи underneath the given елемент will become the target of pointer events.

The effects of masking and clipping differ with respect to pointer-events. A clip path is a geometric boundary, and a given point is clearly either inside or outside that boundary; thus, pointer events must be captured normally over the rendered areas of a clipped елемент, but must not be captured over the clipped areas, as described in the definition of clipping paths. By contrast, a mask is not a binary transition, but a pixel operation, and different behavior for fully transparent and almost-but-not-fully-transparent may be confusingly arbitrary; as a consequence, for елементи with a mask applied, pointer-events must still be captured even in areas where the mask goes to zero opacity. If an author wishes to achieve an effect where the transparent parts of a mask allow pointer-events to pass to an елемент below, a combination of masking and clipping may be used.

The ‘filter’ властивість has no effect on pointer-events processing, and must in this context be treated as if the ‘filter’ wasn't specified.

For example, suppose a circle with a ‘stroke’ of red (i.e., the outline is solid red) and a ‘fill’ of none (i.e., the interior is not painted) is rendered directly on top of a rectangle with a ‘fill’ of blue. The author might want the circle to be the target of pointer events only when the pointer is over the perimeter of the circle. When the pointer is over the interior of the circle, the author might want the underlying rectangle to be the target елемент of pointer events.

The ‘pointer-events’ властивість specifies under what circumstances a given graphics елемент can be the target елемент for a pointer event. It affects the circumstances under which the following are processed:

user interface events such as mouse clicks
dynamic pseudo-classes (i.e., :hover, :active and :focus; [CSS2], section 5.11)
hyperlinks (see Links out of SVG content: the ‘a’ елемент)

‘pointer-events’

Value:	visiblePainted \| visibleFill \| visibleStroke \| visible \| painted \| fill \| stroke \| all \| none \| inherit
Initial:	visiblePainted
Applies to:	graphics елементи
Inherited:	yes
Percentages:	N/A
Media:	visual
Animatable:	yes

visiblePainted: The given елемент can be the target елемент for pointer events when the ‘visibility’ властивість is set to visible and when the pointer is over a "painted" area. The pointer is over a painted area if it is over the interior (i.e., fill) of the елемент and the ‘fill’ властивість has an actual value other than none or it is over the perimeter (i.e., stroke) of the елемент and the ‘stroke’ властивість is set to a value other than none.
visibleFill: The given елемент can be the target елемент for pointer events when the ‘visibility’ властивість is set to visible and when the pointer is over the interior (i.e., fill) of the елемент. The value of the ‘fill’ властивість does not affect event processing.
visibleStroke: The given елемент can be the target елемент for pointer events when the ‘visibility’ властивість is set to visible and when the pointer is over the perimeter (i.e., stroke) of the елемент. The value of the ‘stroke’ властивість does not affect event processing.
visible: The given елемент can be the target елемент for pointer events when the ‘visibility’ властивість is set to visible and the pointer is over either the interior (i.e., fill) or the perimeter (i.e., stroke) of the елемент. The values of the ‘fill’ and ‘stroke’ do not affect event processing.
painted: The given елемент can be the target елемент for pointer events when the pointer is over a "painted" area. The pointer is over a painted area if it is over the interior (i.e., fill) of the елемент and the ‘fill’ властивість has an actual value other than none or it is over the perimeter (i.e., stroke) of the елемент and the ‘stroke’ властивість has an actual value other than none. The value of the ‘visibility’ властивість does not effect event processing.
fill: The given елемент can be the target елемент for pointer events when the pointer is over the interior (i.e., fill) of the елемент. The values of the ‘fill’ and ‘visibility’ властивості do not affect event processing.
stroke: The given елемент can be the target елемент for pointer events when the pointer is over the perimeter (i.e., stroke) of the елемент. The values of the ‘stroke’ and ‘visibility’ властивості do not affect event processing.
all: The given елемент can be the target елемент for pointer events whenever the pointer is over either the interior (i.e., fill) or the perimeter (i.e., stroke) of the елемент. The values of the ‘fill’, ‘stroke’ and ‘visibility’ властивості do not affect event processing.
none: The given елемент does not receive pointer events.

For text елементи, hit-testing is performed on a character cell basis:

The value visiblePainted means that the text string can receive events anywhere within the character cell if either the ‘fill’ властивість is set to a value other than none or the ‘stroke’ властивість is set to a value other than none, with the additional requirement that the ‘visibility’ властивість is set to visible.
The values visibleFill, visibleStroke and visible are equivalent and indicate that the text string can receive events anywhere within the character cell if the ‘visibility’ властивість is set to visible. The values of the ‘fill’ and ‘stroke’ властивості do not affect event processing.
The value painted means that the text string can receive events anywhere within the character cell if either the ‘fill’ властивість is set to a value other than none or the ‘stroke’ властивість is set to a value other than none. The value of the ‘visibility’ властивість does not affect event processing.
The values fill, stroke and all are equivalent and indicate that the text string can receive events anywhere within the character cell. The values of the ‘fill’, ‘stroke’ and ‘visibility’ властивості do not affect event processing.
The value none indicates that the given text does not receive pointer events.

For raster images, hit-testing is either performed on a whole-image basis (i.e., the rectangular area for the image is one of the determinants for whether the image receives the event) or on a per-pixel basis (i.e., the alpha values for pixels under the pointer help determine whether the image receives the event):

The value visiblePainted means that the raster image can receive events anywhere within the bounds of the image if any pixel from the raster image which is under the pointer is not fully transparent, with the additional requirement that the ‘visibility’ властивість is set to visible.
The values visibleFill, visibleStroke and visible are equivalent and indicate that the image can receive events anywhere within the rectangular area for the image if the ‘visibility’ властивість is set to visible.
The value painted means that the raster image can receive events anywhere within the bounds of the image if any pixel from the raster image which is under the pointer is not fully transparent. The value of the ‘visibility’ властивість does not affect event processing.
The values fill, stroke and all are equivalent and indicate that the image can receive events anywhere within the rectangular area for the image. The value of the ‘visibility’ властивість does not affect event processing.
The value none indicates that the image does not receive pointer events.

Note that for raster images, the values of властивості ‘opacity’, ‘fill-opacity’, ‘stroke-opacity’, ‘fill’ and ‘stroke’ do not affect event processing.

16.7 Magnification and panning

Magnification represents a complete, uniform transformation on an SVG document fragment, where the magnify operation scales all graphical елементи by the same amount. A magnify operation has the effect of a supplemental scale and translate transformation placed at the outermost level on the SVG document fragment (i.e., outside the outermost svg елемент).

Panning represents a translation (i.e., a shift) transformation on an SVG document fragment in response to a user interface action.

SVG user agents that operate in interaction-capable user environments are required to support the ability to magnify and pan.

The outermost svg елемент in an SVG document fragment has атрибут ‘zoomAndPan’, which takes the possible values of disable and magnify, with the default being magnify.

If disable, the user agent shall disable any magnification and panning controls and not allow the user to magnify or pan on the given document fragment.

If magnify, in environments that support user interactivity, the user agent shall provide controls to allow the user to perform a "magnify" operation on the document fragment.

If a ‘zoomAndPan’ атрибут is assigned to an inner ‘svg’ елемент, the ‘zoomAndPan’ setting on the inner ‘svg’ елемент will have no effect on the SVG user agent.

Animatable: no.

16.8 Cursors

16.8.1 Вступ to cursors

Some interactive display environments provide the ability to modify the appearance of the pointer, which is also known as the cursor. Three types of cursors are available:

Standard built-in cursors
Platform-specific custom cursors
Platform-independent custom cursors

The ‘cursor’ властивість is used to specify which cursor to use. The ‘cursor’ властивість can be used to reference standard built-in cursors by specifying a keyword such as crosshair or a custom cursor. Custom cursors are referenced via a <funciri> and can point to either an external resource such as a platform-specific cursor file or to a ‘cursor’ елемент, which can be used to define a platform-independent cursor.

16.8.2 The ‘cursor’ властивість

‘cursor’

Value:	[ [<funciri> ,]* [ auto \| crosshair \| default \| pointer \| move \| e-resize \| ne-resize \| nw-resize \| n-resize \| se-resize \| sw-resize \| s-resize \| w-resize\| text \| wait \| help ] ] \| inherit
Initial:	auto
Applies to:	container елементи and graphics елементи
Inherited:	yes
Percentages:	N/A
Media:	visual, interactive
Animatable:	yes

This властивість specifies the type of cursor to be displayed for the pointing device. Values have the following meanings:

auto: The UA determines the cursor to display based on the current context.
crosshair: A simple crosshair (e.g., short line segments resembling a "+" sign).
default: The platform-dependent default cursor. Often rendered as an arrow.
pointer: The cursor is a pointer that indicates a link.
move: Indicates something is to be moved.
e-resize, ne-resize, nw-resize, n-resize, se-resize, sw-resize, s-resize, w-resize: Indicate that some edge is to be moved. For example, the 'se-resize' cursor is used when the movement starts from the south-east corner of the box.
text: Indicates text that can be selected. Often rendered as an I-bar.
wait: Indicates that the program is busy. Often rendered as a watch or hourglass.
help: Help is available for the object under the cursor. Often rendered as a question mark or a balloon.
<funciri>: The user agent retrieves the cursor from the resource designated by the URI. If the user agent cannot handle the first cursor of a list of cursors, it shall attempt to handle the second, etc. If the user agent cannot handle any user-defined cursor, it must use the generic cursor at the end of the list.

P { cursor : url("mything.cur"), url("second.svg#curs"), text; }

The ‘cursor’ властивість for SVG is identical to the ‘cursor’ властивість defined in CSS2 ([CSS2], section 18.1), with the additional requirement that SVG user agents must support cursors defined by the SVG ‘cursor’ елемент. This gives a single, cross-platform, interoperable cursor format, with PNG as the raster component.

16.8.3 The ‘cursor’ елемент

The ‘cursor’ елемент can be used to define a platform-independent custom cursor. A recommended approach for defining a platform-independent custom cursor is to create a PNG image [PNG] and define a ‘cursor’ елемент that references the PNG image and identifies the exact position within the image which is the pointer position (i.e., the hot spot).

The PNG format is recommended because it supports the ability to define a transparency mask via an alpha channel. If a different image format is used, this format should support the definition of a transparency mask (two options: provide an explicit alpha channel or use a particular pixel color to indicate transparency). If the transparency mask can be determined, the mask defines the shape of the cursor; otherwise, the cursor is an opaque rectangle. Typically, the other pixel information (e.g., the R, G and B channels) defines the colors for those parts of the cursor which are not masked out. Note that cursors usually contain at least two colors so that the cursor can be visible over most backgrounds.

‘cursor’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

DOM Інтерфейсs:

SVGCursorElement

Attribute definitions:

x = "<coordinate>": The x-coordinate of the position in the cursor's coordinate system which represents the precise position that is being pointed to.
If the атрибут is not specified, the effect is as if a value of '0' were specified.
Animatable: yes.
y = "<coordinate>": The y-coordinate of the position in the cursor's coordinate system which represents the precise position that is being pointed to.
If the атрибут is not specified, the effect is as if a value of '0' were specified.
Animatable: yes.
xlink:href = "<funciri>": A Functional IRI reference to the file or елемент which provides the image of the cursor.
Animatable: yes.

SVG user agents are required to support PNG format images as targets of the ‘xlink:href’ атрибут.

16.9 DOM interfaces

16.9.1 Інтерфейс SVGCursorElement

The SVGCursorElement interface corresponds to the ‘cursor’ елемент.

interface SVGCursorElement : SVGElement,
                             SVGURIReference,
                             SVGTests,
                             SVGExternalResourcesRequired {
  readonly атрибут SVGAnimatedLength x;
  readonly атрибут SVGAnimatedLength y;
};

Attributes:

x (readonly SVGAnimatedLength): Corresponds to атрибут ‘x’ on the given ‘cursor’ елемент.
y (readonly SVGAnimatedLength): Corresponds to атрибут ‘y’ on the given ‘cursor’ елемент.

17 Linking

17.1 References
17.2 Links out of SVG content: the ‘a’ елемент
17.3 Linking into SVG content: IRI fragments and SVG views
17.4 DOM interfaces
- 17.4.1 Інтерфейс SVGAElement
- 17.4.2 Інтерфейс SVGViewElement

17.1 References

17.1.1 Огляд

On the Internet, resources are identified using IRIs (Internationalized Resource Identifiers). For example, an SVG file called someDrawing.svg located at http://example.com might have the following IRI:

http://example.com/someDrawing.svg

An IRI can also address a particular елемент within an XML document by including an IRI fragment identifier as part of the IRI. An IRI which includes an IRI fragment identifier consists of an optional base IRI, followed by a "#" character, followed by the IRI fragment identifier. For example, the following IRI can be used to specify the елемент whose ID is "Lamppost" within file someDrawing.svg:

http://example.com/someDrawing.svg#Lamppost

17.1.2 IRIs and URIs

Internationalized Resource Identifiers (IRIs) are a more generalized complement to Uniform Resource Identifiers (URIs). An IRI is a sequence of characters from the Universal Character Set [UNICODE]. A URI is constructed from a much more restricted set of characters. All URIs are already conformant IRIs. A mapping from IRIs to URIs is defined by the IRI specification, which means that IRIs can be used instead of URIs in XML documents, to identify resources. IRIs can be converted to URIs for resolution on a network, if the protocol does not support IRIs directly.

Previous versions of SVG, following XLink, defined an IRI reference type as a URI or as a sequence of characters which must result in an IRI after a particular escaping procedure was applied. The escaping procedure was repeated in the XLink 1.0 specification [XLINK], and in the W3C XML Schema Part 2: Datatypes specification [SCHEMA2]. This copying introduced the possibility of error and divergence, but was done because the IRI specification was not yet standardized.

In this specification, the correct term IRI is used for this "URI or sequence of characters plus an algorithm" and the escaping method, which turns IRIs into URIs, is defined by reference to the IRI specification [RFC3987], which has since become an IETF Proposed Standard. Other W3C specifications are expected to be revised over time to remove these duplicate descriptions of the escaping procedure and to refer to IRI directly.

17.1.3 Syntactic forms: IRI and FuncIRI

IRIs are used in the ‘xlink:href’ атрибут. Some атрибути allow both IRIs and text strings as content. To disambiguate a text string from a relative IRI, the functional notation <FuncIRI> is used. This is simply an IRI delimited with a functional notation. Note: For historical reasons, the delimiters are "url(" and ")", for compatibility with the CSS specifications. The FuncIRI form is used in presentation атрибути .

SVG makes extensive use of IRI references, both absolute and relative, to other objects. For example, to fill a rectangle with a linear gradient, you first define a ‘linearGradient’ елемент and give it an ID, as in:

<linearGradient xml:id="MyGradient">...</linearGradient>

You then reference the linear gradient as the value of the ‘fill’ властивість for the rectangle, as in the following example:

<rect fill="url(#MyGradient)"/>

SVG supports two types of IRI references:

local IRI references, where the IRI reference does not contain an <absoluteIRI> or <relativeIRI> and thus only contains a fragment identifier (i.e., #<елементID> or #xpointer(id<елементID>))
non-local IRI references, where the IRI reference does contain an <absoluteIRI> or <relativeIRI>

17.1.4 Processing of IRI references

The following rules apply to the processing of IRI references:

IRI references to nodes that do not exist shall be treated as invalid references.
IRI references to елементи which are inappropriate targets for the given reference shall be treated as invalid references (see list below for appropriate targets). For example, the ‘clip-path’ властивість can only refer to ‘clipPath’ елементи. The властивість setting clip-path:url(#MyElement) is an invalid reference if the referenced елемент is not a ‘clipPath’.
IRI references that directly or indirectly reference themselves are treated as invalid circular references.

The following list describes the елементи and властивості that allow IRI references and the valid target types for those references:

the ‘a’ елемент can reference any local or non-local resource
the ‘altGlyph’ елемент must reference either an ‘altGlyphDef’ елемент or a ‘glyph’ елемент
the ‘animate’ елемент (see Identifying the target елемент for an animation for reference rules)
the ‘animateColor’ елемент (see Identifying the target елемент for an animation for reference rules)
the ‘animateMotion’ елемент (see Identifying the target елемент for an animation for reference rules)
the ‘animateTransform’ елемент (see Identifying the target елемент for an animation for reference rules)
the ‘clip-path’ властивість must reference a ‘clipPath’ елемент
the ‘color-profile’ елемент must reference an ICC profile resource
the ‘color-profile’ властивість must reference an ICC profile resource or a ‘color-profile’ елемент
the 'src' descriptor on an @color-profile definition must reference an ICC profile resource or a ‘color-profile’ елемент
the ‘cursor’ елемент must reference a resource that can provide an image for the cursor graphic
the ‘cursor’ властивість must reference a resource that can provide an image for the cursor graphic
the ‘feImage’ елемент must reference any local or non-local resource
the ‘fill’ властивість (see Specifying paint for reference rules)
the ‘filter’ елемент must reference a ‘filter’ елемент
the ‘filter’ властивість must reference a ‘filter’ елемент
the ‘image’ елемент must reference any local or non-local resource
the ‘linearGradient’ елемент must reference a ‘linearGradient’ or ‘radialGradient’ елемент
the ‘marker’, ‘marker-start’, ‘marker-mid’ and ‘marker-end’ властивості must reference a ‘marker’ елемент.
the ‘mask’ властивість must reference a ‘mask’ елемент
the ‘pattern’ елемент must reference a ‘pattern’ елемент
the ‘radialGradient’ елемент must reference a ‘linearGradient’ or ‘radialGradient’ елемент
the ‘script’ елемент must reference an external resource that provides the script content
the ‘stroke’ властивість (see Specifying paint for reference rules)
the ‘textPath’ елемент must reference a ‘path’ елемент
the ‘tref’ елемент can reference any SVG елемент
the ‘set’ елемент (see Identifying the target елемент for an animation for reference rules)
the ‘use’ елемент can reference any local or non-local resource

The following rules apply to the processing of invalid IRI references:

An invalid local IRI reference (i.e., an invalid references to a node within the current document) represents an error (see Error processing), apart from the ‘xlink:href’ атрибут on the ‘a’ елемент and the властивості that allow for backup values in the case where the IRI reference is invalid (see ‘fill’ and ‘stroke’).
An invalid circular IRI reference represents an error (see Error processing).
When атрибут ‘externalResourcesRequired’ has been set to 'true' on the referencing елемент or one of its ancestors, then an unresolved external IRI reference (i.e., a resource that cannot be located) represents an error (see Error processing).

17.1.5 IRI reference атрибути

IRI references are normally specified with an ‘href’ атрибут in the XLink [XLink] namespace. For example, if the prefix of 'xlink' is used for атрибути in the XLink namespace, then the атрибут is be specified as ‘xlink:href’. The value of this атрибут forms a reference for the desired resource (or secondary resource, if there is a fragment identifier).

The value of the ‘href’ атрибут must be an Internationalized Resource Identifier.

If the protocol, such as HTTP, does not support IRIs directly, the IRI is converted to a URI by the SVG implementation, as described in section 3.1 of the IRI specification [RFC3987.

Because it is impractical for any application to check that a value is an IRI reference, this specification follows the lead of the IRI Specification in this matter and imposes no such conformance testing requirement on SVG applications.

If the IRI reference is relative, its absolute version must be computed by the method described in XML Base before use [XML-BASE].

xlink:type = "simple"

Identifies the type of XLink being used. In SVG 1.1, only simple links are available. Links are simple links by default, so the атрибут xlink:type="simple" is optional and may be omitted on simple links. Refer to the XML Linking Language (XLink) [XLINK].

Animatable: no.

xlink:role = "<IRI>"

Animatable: no.

xlink:arcrole = "<IRI>"

An optional IRI reference that identifies some resource that describes the intended властивість. The value must be an IRI reference as defined in [RFC3987], except that if the IRI scheme used is allowed to have absolute and relative forms, the IRI portion must be absolute. When no value is supplied, no particular role value shall be inferred. The arcrole атрибут corresponds to the [RDF-PRIMER] notion of a властивість, where the role can be interpreted as stating that "starting-resource HAS arc-role ending-resource." This contextual role can differ from the meaning of an ending resource when taken outside the context of this particular arc. For example, a resource might generically represent a "person," but in the context of a particular arc it might have the role of "mother" and in the context of a different arc it might have the role of "daughter." Refer to the XML Linking Language (XLink) [XLINK].

Animatable: no.

xlink:title = "<anything>"

The title атрибут shall be used to describe the meaning of a link or resource in a human-readable fashion, along the same lines as the role or arcrole атрибут. A value is optional; if a value is supplied, it shall contain a string that describes the resource. In general it is preferable to use a ‘title’ child елемент rather than a ‘title’ атрибут. The use of this information is highly dependent on the type of processing being done. It may be used, for example, to make titles available to applications used by visually impaired users, or to create a table of links, or to present help text that appears when a user lets a mouse pointer hover over a starting resource. Refer to the XML Linking Language (XLink) [XLINK].

Animatable: no.

xlink:show = "new' | 'replace' | 'embed' | 'other' | 'none'

This атрибут is provided for backwards compatibility with SVG 1.1. It provides documentation to XLink-aware processors. In case of a conflict, the target атрибут has priority, since it can express a wider range of values. Refer to the XML Linking Language (XLink) [XLINK].

Animatable: no.

xlink:actuate = "onLoad'

This атрибут is provided for backwards compatibility with SVG 1.1. It provides documentation to XLink-aware processors. Refer to the XML Linking Language (XLink) [XLINK].

Animatable: no.

In all cases, for compliance with either the "Namespaces in XML 1.0" or the "Namespaces in XML 1.1" Recommendation [XML-NS10][XML-NS], an explicit XLink namespace declaration must be provided whenever one of the above XLink атрибути is used within SVG content. One simple way to provide such an XLink namespace declaration is to include an ‘xmlns’ атрибут for the XLink namespace on the ‘svg’ елемент for content that uses XLink атрибути. For example:

<svg xmlns:xlink="http://www.w3.org/1999/xlink" ...>
  <image xlink:href="foo.png" .../>
</svg>

17.2 Links out of SVG content: the ‘a’ елемент

SVG provides an ‘a’ елемент, to indicate links (also known as hyperlinks or Web links). The ‘a’ елемент may contain any елемент that its parent may contain, except itself.

SVG uses XLink ([XLink]) for all link definitions. SVG 1.1 only requires that user agents support XLink's notion of simple links. Each simple link associates exactly two resources, one local and one remote, with an arc going from the former to the latter.

A simple link is defined for each separate rendered елемент contained within the ‘a’ елемент; thus, if the ‘a’ елемент contains three ‘circle’ елементи, a link is created for each circle. For each rendered елемент within an ‘a’ елемент, the given rendered елемент is the local resource (the source anchor for the link).

The remote resource (the destination for the link) is defined by a IRI specified by the XLink ‘xlink:href’ атрибут on the ‘a’ елемент. The remote resource may be any Web resource (e.g., an image, a video clip, a sound bite, a program, another SVG document, an HTML document, an елемент within the current document, an елемент within a different document, etc.). By activating these links (by clicking with the mouse, through keyboard input, voice commands, etc.), users may visit these resources.

Example link01 assigns a link to an ellipse.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="5cm" height="3cm" viewBox="0 0 5 3" version="1.1"
     xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
  <desc>Example link01 - a link on an ellipse
  </desc>
  <rect x=".01" y=".01" width="4.98" height="2.98" 
        fill="none" stroke="blue"  stroke-width=".03"/>
  <a xlink:href="http://www.w3.org">
    <ellipse cx="2.5" cy="1.5" rx="2" ry="1"
             fill="red" />
  </a>
</svg>

Example link01

View this example as SVG (SVG-enabled browsers only)

If the above SVG file is viewed by a user agent that supports both SVG and HTML, then clicking on the ellipse will cause the current window or frame to be replaced by the W3C home page.

‘a’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
graphical event атрибути — ‘onfocusin’, ‘onfocusout’, ‘onactivate’, ‘onclick’, ‘onmousedown’, ‘onmouseup’, ‘onmouseover’, ‘onmousemove’, ‘onmouseout’, ‘onload’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘class’
‘style’
‘externalResourcesRequired’
‘transform’
‘xlink:href’
‘xlink:show’
‘xlink:actuate’
‘target’

DOM Інтерфейсs:

SVGAElement

Attribute definitions:

xlink:show = "new" | "replace"

This атрибут provides documentation to XLink-aware processors. If target="_blank" then use xlink:show="new" else use 'replace'. In case of a conflict, the target атрибут has priority, since it can express a wider range of values. Refer to the XML Linking Language (XLink) [XLINK].

Animatable: no.

xlink:actuate = "onRequest"

This атрибут provides documentation to XLink-aware processors that an application should traverse from the starting resource to the ending resource only on a post-loading event triggered for the purpose of traversal. Refer to the XML Linking Language (XLink) [XLINK].

Animatable: no.

xlink:href = "<IRI>"

The location of the referenced object, expressed as an IRI reference.

Animatable: yes.

This атрибут should be used when there are multiple possible targets for the ending resource, such as when the parent document is a multi-frame HTML or XHTML document. This атрибут specifies the name or portion of the target window, frame, pane, tab, or other relevant presentation context (e.g., an HTML or XHTML frame, iframe, or object елемент) into which a document is to be opened when the link is activated:

_replace: The current SVG image is replaced by the linked content in the same rectangular area in the same frame as the current SVG image.
_self: The current SVG image is replaced by the linked content in the same frame as the current SVG image. If the атрибут is not specified, '_self' is assumed.
_parent: The immediate frameset parent of the SVG image is replaced by the linked content.
_top: The content of the full window or tab, including any frames, is replaced by the linked content
_blank: A new un-named window or tab is requested for the display of the linked content. If this fails, the result is the same as _top
<XML-Name>: Specifies the name of the frame, pane, or other relevant presentation context for display of the linked content. If this already exists, it is re-used, replacing the existing content. If it does not exist, it is created (the same as '_blank', except that it now has a name).

Note: The value '_new' is not a legal value for target (use '_blank').

Animatable: yes.

17.3 Linking into SVG content: IRI fragments and SVG views

17.3.1 Вступ: IRI fragments and SVG views

Because SVG content often represents a picture or drawing of something, a common need is to link into a particular view of the document, where a view indicates the initial transformations so as to present a closeup of a particular section of the document.

17.3.2 SVG fragment identifiers

To link into a particular view of an SVG document, the IRI fragment identifier needs to be a correctly formed SVG fragment identifier. An SVG fragment identifier defines the meaning of the "selector" or "fragment identifier" portion of IRIs that locate resources of MIME media type "image/svg+xml".

An SVG fragment identifier can come in two forms:

Shorthand bare name form of addressing (e.g., MyDrawing.svg#MyView). This form of addressing, which allows addressing an SVG елемент by its ID, is compatible with the fragment addressing mechanism for older versions of HTML.
SVG view specification (e.g., MyDrawing.svg#svgView(viewBox(0,200,1000,1000))). This form of addressing specifies the desired view of the document (e.g., the region of the document to view, the initial zoom level) completely within the SVG fragment specification. The contents of the SVG view specification are the five parameter specifications, viewBox(...), preserveAspectRatio(...), transform(...), zoomAndPan(...) and viewTarget(...), whose parameters have the same meaning as the corresponding атрибути on a ‘view’ елемент, or, in the case of transform(...), the same meaning as the corresponding атрибут has on a ‘g’ елемент).

An SVG fragment identifier is defined as follows:

SVGFragmentIdentifier ::= BareName |
                          SVGViewSpec
                
BareName ::= XML_Name
SVGViewSpec ::= 'svgView(' SVGViewAttributes ')'
SVGViewAttributes ::= SVGViewAttribute |
                      SVGViewAttribute ';' SVGViewAttributes
                      
SVGViewAttribute ::= viewBoxSpec |
                     preserveAspectRatioSpec |
                     transformSpec |
                     zoomAndPanSpec |
                     viewTargetSpec
viewBoxSpec ::= 'viewBox(' ViewBoxParams ')'
preserveAspectRatioSpec = 'preserveAspectRatio(' AspectParams ')'
transformSpec ::= 'transform(' TransformParams ')'
zoomAndPanSpec ::= 'zoomAndPan(' ZoomAndPanParams ')'
viewTargetSpec ::= 'viewTarget(' ViewTargetParams ')'

where:

ViewBoxParams corresponds to the parameter values for the ‘viewBox’ атрибут on the ‘view’ елемент. For example, viewBox(0,0,200,200).
AspectParams corresponds to the parameter values for the ‘preserveAspectRatio’ атрибут on the ‘view’ елемент. For example, preserveAspectRatio(xMidYMid).
TransformParams corresponds to the parameter values for the ‘transform’ атрибут that is available on many елементи. For example, transform(scale(5)).
ZoomAndPanParams corresponds to the parameter values for the ‘zoomAndPan’ атрибут on the ‘view’ елемент. For example, zoomAndPan(magnify).
ViewTargetParams corresponds to the parameter values for the ‘viewTarget’ атрибут on the ‘view’ елемент. For example, viewTarget(MyElementID).

Spaces are not allowed in fragment specifications; thus, commas are used to separate numeric values within an SVG view specification (e.g., #svgView(viewBox(0,0,200,200))) and semicolons are used to separate атрибути (e.g., #svgView(viewBox(0,0,200,200);preserveAspectRatio(none))).

Semicolons used to separate 'SVGViewAttribute' in SVG fragments may be url-escaped (as %3B); this is useful when animating a (semi-colon separated) list of IRIs because otherwise the semicolon would be interpreted as a list separator.

The five types of SVGViewAttribute may occur in any order, but each type may only occur at most one time in a correctly formed SVGViewSpec.

When a source document performs a link into an SVG document, for example via an HTML anchor елемент ([HTML4], section 12.2; i.e., <a href=...> елемент in HTML) or an XLink specification [XLINK], then the SVG fragment identifier specifies the initial view into the SVG document, as follows:

If no SVG fragment identifier is provided (e.g, the specified IRI did not contain a "#" character, such as MyDrawing.svg), then the initial view into the SVG document is established using the view specification атрибути (i.e., ‘viewBox’, etc.) on the outermost svg елемент.
If the SVG fragment identifier addresses a ‘view’ елемент within an SVG document (e.g., MyDrawing.svg#MyView or MyDrawing.svg#xpointer(id('MyView'))) then the closest ancestor ‘svg’ елемент is displayed in the viewport. Any view specification атрибути included on the given ‘view’ елемент override the corresponding view specification атрибути on the closest ancestor ‘svg’ елемент.
If the SVG fragment identifier addresses specific SVG view (e.g., MyDrawing.svg#svgView(viewBox(0,200,1000,1000))), then the document fragment defined by the closest ancestor ‘svg’ елемент is displayed in the viewport using the SVG view specification provided by the SVG fragment identifier.
If the SVG fragment identifier addresses any елемент other than a ‘view’ елемент, then the document defined by the closest ancestor ‘svg’ елемент is displayed in the viewport using the view specification атрибути on that ‘svg’ елемент.

17.3.3 Predefined views: the ‘view’ елемент

The ‘view’ елемент is defined as follows:

‘view’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
‘externalResourcesRequired’
‘viewBox’
‘preserveAspectRatio’
‘zoomAndPan’
‘viewTarget’

DOM Інтерфейсs:

SVGViewElement

Attribute definitions:

viewTarget = "XML_Name [XML_NAME]*": Indicates the target object associated with the view.
Animatable: no.

17.3.4 Highlighting views

It is helpful to users if the target елемент(s) are highlighted. The visual styling of this highlight should be decided by the document author, because the SVG User Agent has no way to determine what changes would make the елементи more visible.

The CSS :target selector ([SELECTORS], section 6.2.2) may be used in a stylesheet to provide alternate styling for елементи which are the target of links. For example:

<style type="text/css">
#foo:target {filter: url(#glow)}
/* when the елемент with id foo is linked to, use a glow filter */

.bar :target {stroke: green; fill-opacity: 0.5}
/* when any descendants of елементи with class bar are linked
   to, make the fill partly transparent and use a green stroke */

:target {stroke: red }
/* for everything else, just use a red stroke */ 
</style>

17.4 DOM interfaces

17.4.1 Інтерфейс SVGAElement

The SVGAElement interface corresponds to the ‘a’ елемент.

interface SVGAElement : SVGElement,
                        SVGURIReference,
                        SVGTests,
                        SVGLangSpace,
                        SVGExternalResourcesRequired,
                        SVGStylable,
                        SVGTransformable {
  readonly атрибут SVGAnimatedString target;
};

Attributes:

target (readonly SVGAnimatedString): Corresponds to атрибут ‘target’ on the given ‘a’ елемент.

17.4.2 Інтерфейс SVGViewElement

The SVGViewElement interface corresponds to the ‘view’ елемент.

interface SVGViewElement : SVGElement,
                           SVGExternalResourcesRequired,
                           SVGFitToViewBox,
                           SVGZoomAndPan {
  readonly атрибут SVGStringList viewTarget;
};

Attributes:

viewTarget (readonly SVGStringList): Corresponds to атрибут ‘viewTarget’ on the given ‘view’ елемент. A list of DOMString values which contain the names listed in the ‘viewTarget’ атрибут. Each of the DOMString values can be associated with the corresponding елемент using the getElementById() method call.

18 Scripting

18.1 Specifying the scripting language
- 18.1.1 Specifying the default scripting language
- 18.1.2 Local declaration of a scripting language
18.2 The ‘script’ елемент
18.3 Event handling
18.4 Event атрибути
18.5 DOM interfaces
- 18.5.1 Інтерфейс SVGScriptElement
- 18.5.2 Інтерфейс SVGZoomEvent

18.1 Specifying the scripting language

18.1.1 Specifying the default scripting language

The ‘contentScriptType’ атрибут on the ‘svg’ елемент specifies the default scripting language for the given document fragment.

contentScriptType = "content-type": Identifies the default scripting language for the given SVG document fragment. This атрибут sets the default scripting language used to process the value strings in event атрибути. This language must be used for all instances of script that do not specify their own scripting language. The value content-type specifies a media type, per MIME Part Two: Media Types [RFC2046]. The default value is 'application/ecmascript' [RFC4329].
Animatable: no.

18.1.2 Local declaration of a scripting language

It is also possible to specify the scripting language for each individual ‘script’ елемент by specifying a ‘type’ on the ‘script’ елемент.

18.2 The ‘script’ елемент

A ‘script’ елемент is equivalent to the ‘script’ елемент in HTML and thus is the place for scripts (e.g., ECMAScript). Any functions defined within any ‘script’ елемент have a "global" scope across the entire current document.

Example script01 defines a function circle_click which is called by the ‘onclick’ event атрибут on the ‘circle’ елемент. The drawing below on the left is the initial image. The drawing below on the right shows the result after clicking on the circle.

Note that this example demonstrates the use of the ‘onclick’ event атрибут for explanatory purposes. The example presupposes the presence of an input device with the same behavioral characteristics as a mouse, which will not always be the case. To support the widest range of users, the ‘onactivate’ event атрибут should be used instead of the ‘onclick’ event атрибут.

Before attempting to execute the ‘script’ елемент the resolved media type value for ‘type’ must be inspected. If the SVG user agent does not support the scripting language then the ‘script’ елемент must not be executed.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="6cm" height="5cm" viewBox="0 0 600 500"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example script01 - invoke an ECMAScript function from an onclick event
  </desc>
  <!-- ECMAScript to change the radius with each click -->
  <script type="application/ecmascript"> <![CDATA[
    function circle_click(evt) {
      var circle = evt.target;
      var currentRadius = circle.getAttribute("r");
      if (currentRadius == 100)
        circle.setAttribute("r", currentRadius*2);
      else
        circle.setAttribute("r", currentRadius*0.5);
    }
  ]]> </script>

  <!-- Outline the drawing area with a blue line -->
  <rect x="1" y="1" width="598" height="498" fill="none" stroke="blue"/>

  <!-- Act on each click event -->
  <circle onclick="circle_click(evt)" cx="300" cy="225" r="100"
          fill="red"/>

  <text x="300" y="480" 
        font-family="Verdana" font-size="35" text-anchor="middle">

    Click on circle to change its size
  </text>
</svg>

Example script01

‘script’

Categories:

None

Content модель:

Any елементи or character data.

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘externalResourcesRequired’
‘type’
‘xlink:href’

DOM Інтерфейсs:

SVGScriptElement

Attribute definitions:

type = "content-type": Identifies the scripting language for the given ‘script’ елемент. The value content-type specifies a media type, per Multipurpose Internet Mail Extensions (MIME) Part Two [RFC2046]. If a ‘type’ is not provided, the value of ‘contentScriptType’ on the ‘svg’ елемент shall be used, which in turn defaults to "application/ecmascript" [RFC4329]. If a ‘script’ елемент falls outside of the outermost svg елемент and the ‘type’ is not provided, the ‘type’ must default to "application/ecmascript" [RFC4329].
Animatable: no.
xlink:href = "<iri>": An IRI reference to an external resource containing the script code.
Animatable: no.

18.3 Event handling

Events can cause scripts to execute when either of the following has occurred:

Event атрибути such as ‘onclick’ or ‘onload’ are assigned to particular елементи, where the values of the event атрибути are script which is executed when the given event occurs.
Event listeners as described in DOM Level 2 Events [DOM2EVENTS] are defined which are invoked when a given event happens on a given object.

Related sections of the spec:

User interface events describes how an SVG user agent handles events such as pointer movements events (e.g., mouse movement) and activation events (e.g., mouse click).
Relationship with DOM2 events describes what parts of DOM are supported by SVG and how to register event listeners.

18.4 Event атрибути

The following event атрибути are available on many SVG елементи.

The complete list of events that are part of the SVG language and SVG DOM and descriptions of those events is provided in Complete list of supported events.

18.4.1 Event атрибут for the SVGLoad event

Below is the definition for the ‘onload’ event атрибут. It can be specified on all of the animation елементи and most of the graphics елементи and container елементи. The ‘onload’ event атрибут is classified as both a graphical event атрибут and an animation event атрибут. (See the definition for each елемент to determine whether it can have a graphical event атрибут specified on it.)

Attribute definitions:

onload = "<anything>": Specifies some script to execute when "bubbling" or "at target" phase listeners for the SVGLoad event are fired on the елемент the атрибут is specified on.
Animatable: no.

18.4.2 Event атрибути on graphics and container елементи

Below are the definitions for the graphical event атрибути. These can be specified on most graphics елементи and container елементи. (See the definition for each елемент to determine whether it can have a graphical event атрибут specified on it.)

Note that ‘onload’, defined above, is also classified as a graphical event атрибут.

Attribute definitions:

onfocusin = "<anything>"
onfocusout = "<anything>"
onactivate = "<anything>"
onclick = "<anything>"
onmousedown = "<anything>"
onmouseup = "<anything>"
onmouseover = "<anything>"
onmousemove = "<anything>"
onmouseout = "<anything>": Specifies some script to execute when "bubbling" or "at target" phase listeners for the corresponding event are fired on the елемент the атрибут is specified on. See the Complete list of support events to determine which event each of these event атрибути corresponds to.
Animatable: no.

18.4.3 Document-level event атрибути

Below are the definitions for the document event атрибути. These can be specified only on ‘svg’ елементи.

Attribute definitions:

onunload = "<anything>"
onabort = "<anything>"
onerror = "<anything>"
onresize = "<anything>"
onscroll = "<anything>"
onzoom = "<anything>": Specifies some script to execute when "bubbling" or "at target" phase listeners for the corresponding event are fired on the елемент the атрибут is specified on. See the Complete list of support events to determine which event each of these event атрибути corresponds to.
Animatable: no.

18.4.4 Animation event атрибути

Below are the definitions for the animation event атрибути. These can be specified on the animation елементи.

Note that ‘onload’, defined above, is also classified as an animation event атрибут.

Attribute definitions:

onbegin = "<anything>"
onend = "<anything>"
onrepeat = "<anything>": Specifies some script to execute when "bubbling" or "at target" phase listeners for the corresponding event are fired on the елемент the атрибут is specified on. See the Complete list of support events to determine which event each of these event атрибути corresponds to.
Animatable: no.

18.5 DOM interfaces

18.5.1 Інтерфейс SVGScriptElement

The SVGScriptElement interface corresponds to the ‘script’ елемент.

interface SVGScriptElement : SVGElement,
                             SVGURIReference,
                             SVGExternalResourcesRequired {
  атрибут DOMString type setraises(DOMException);
};

Attributes:

type (DOMString)

Corresponds to атрибут ‘type’ on the given ‘script’ елемент.

Exceptions on setting

DOMException, code NO_MODIFICATION_ALLOWED_ERR: Raised on an attempt to change the value of a read only атрибут.

18.5.2 Інтерфейс SVGZoomEvent

A DOM consumer can use the hasFeature of the DOMImplementation interface to determine whether the SVG zoom event set has been implemented by a DOM implementation. The feature string for this event set is "SVGZoomEvents". This string is also used with the createEvent method.

The zoom event handler occurs before the zoom event is processed. The remainder of the DOM represents the previous state of the document. The document will be updated upon normal return from the event handler.

The UI event type for a zoom event is:

SVGZoom

The zoom event occurs when the user initiates an action which causes the current view of the SVG document fragment to be rescaled. Event handlers are only recognized on ‘svg’ елементи. See SVGZoom event.

Bubbles: Yes
Cancelable: No
Context Info: zoomRectScreen, previousScale, previousTranslate, newScale, newTranslate, screenX, screenY, clientX, clientY, altKey, ctrlKey, shiftKey, metaKey, relatedNode.
(screenX, screenY, clientX and clientY indicate the center of the zoom area, with clientX and clientY in viewport coordinates for the corresponding ‘svg’ елемент. relatedNode is the corresponding ‘svg’ елемент.)

interface SVGZoomEvent : UIEvent {
  readonly атрибут SVGRect zoomRectScreen;
  readonly атрибут float previousScale;
  readonly атрибут SVGPoint previousTranslate;
  readonly атрибут float newScale;
  readonly атрибут SVGPoint newTranslate;
};

Attributes:

zoomRectScreen (readonly SVGRect): The specified zoom rectangle in screen units.

The SVGRect object is read only.
previousScale (readonly float): The scale factor from previous zoom operations that was in place before the zoom operation occurred.
previousTranslate (readonly SVGPoint): The translation values from previous zoom operations that were in place before the zoom operation occurred.

The SVGPoint object is read only.
newScale (readonly float): The scale factor that will be in place after the zoom operation has been processed.
newTranslate (readonly SVGPoint): The translation values that will be in place after the zoom operation has been processed.

The SVGPoint object is read only.

19 Animation

19.1 Вступ
19.2 Animation елементи
19.3 Animation using the SVG DOM
19.4 DOM interfaces

19.1 Вступ

Because the Web is a dynamic medium, SVG supports the ability to change vector graphics over time. SVG content can be animated in the following ways:

Using SVG's animation елементи. SVG document fragments can describe time-based modifications to the document's елементи. Using the various animation елементи, you can define motion paths, fade-in or fade-out effects, and objects that grow, shrink, spin or change color.
Using the SVG DOM. The SVG DOM conforms to key aspects of the Document Object Model (DOM) Level 1 [DOM1] and Document Object Model (DOM) Level 2 [DOM2] specifications. Every атрибут and style sheet setting is accessible to scripting, and SVG offers a set of additional DOM interfaces to support efficient animation via scripting. As a result, virtually any kind of animation can be achieved. The timer facilities in scripting languages such as ECMAScript can be used to start up and control the animations [ECMA-262]. (See example below.)
SVG has been designed to allow SMIL [SMIL] to use animated or static SVG content as media components.

19.2 Animation елементи

19.2.1 Огляд

SVG's animation елементи were developed in collaboration with the W3C Synchronized Multimedia (SYMM) Working Group, developers of the Synchronized Multimedia Integration Language (SMIL) 3.0 Specification [SMIL].

The SYMM Working Group, in collaboration with the SVG Working Group, has authored the SMIL Animation specification [SMILANIM], which represents a general-purpose XML animation feature set. SVG incorporates the animation features defined in the SMIL Animation specification and provides some SVG-specific extensions.

For an introduction to the approach and features available in any language that supports SMIL Animation, see SMIL Animation overview and SMIL Animation animation модель ([SMILANIM], sections 2 and 3). For the list of animation features which go beyond SMIL Animation, see SVG extensions to SMIL Animation.

19.2.2 Relationship to SMIL Animation

SVG is a host language in terms of SMIL Animation and therefore introduces additional constraints and features as permitted by that specification. Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for SVG's animation елементи and атрибути is the SMIL Animation specification [SMILANIM].

SVG supports the following four animation елементи which are defined in the SMIL Animation specification:

‘animate’	allows scalar атрибути and властивості to be assigned different values over time
‘set’	a convenient shorthand for ‘animate’, which is useful for assigning animation values to non-numeric атрибути and властивості, such as the ‘visibility’ властивість
‘animateMotion’	moves an елемент along a motion path
‘animateColor’	modifies the color value of particular атрибути or властивості over time

Although SVG defines ‘animateColor’, its use is deprecated in favor of simply using the ‘animate’ елемент to target властивості that can take color values.

Additionally, SVG includes the following compatible extensions to SMIL Animation:

‘animateTransform’	modifies one of SVG's transformation атрибути over time, such as the ‘transform’ атрибут
‘path’ атрибут	SVG allows any feature from SVG's path data syntax to be specified in a ‘path’ атрибут to the ‘animateMotion’ елемент (SMIL Animation only allows a subset of SVG's path data syntax within a ‘path’ атрибут)
‘mpath’ елемент	SVG allows an ‘animateMotion’ елемент to contain a child ‘mpath’ елемент which references an SVG ‘path’ елемент as the definition of the motion path
‘keyPoints’ атрибут	SVG adds a ‘keyPoints’ атрибут to the ‘animateMotion’ to provide precise control of the velocity of motion path animations
‘rotate’ атрибут	SVG adds a ‘rotate’ атрибут to the ‘animateMotion’ to control whether an object is automatically rotated so that its x-axis points in the same direction (or opposite direction) as the directional tangent vector of the motion path

For compatibility with other aspects of the language, SVG uses IRI references via an ‘xlink:href’ атрибут to identify the елементи which are to be targets of the animations, as allowed in SMIL 3.0.

SMIL Animation requires that the host language define the meaning for document begin and the document end. Since an ‘svg’ is sometimes the root of the XML document tree and other times can be a component of a parent XML grammar, the document begin for a given SVG document fragment is defined to be the exact time at which the ‘svg’ елемент's SVGLoad event is triggered. The document end of an SVG document fragment is the point at which the document fragment has been released and is no longer being processed by the user agent. Якever, nested ‘svg’ елементи within an SVG document do not constitute document fragments in this sense, and do not define a separate document begin; all times within the nested SVG fragment are relative to the document time defined for the root ‘svg’ елемент.

For SVG, the term presentation time indicates the position in the timeline relative to the document begin of a given document fragment.

SVG defines more constrained error processing than is defined in the SMIL Animation specification [SMILANIM]. SMIL Animation defines error processing behavior where the document continues to run in certain error situations, whereas all animations within an SVG document fragment will stop in the event of any error within the document (see Error processing).

19.2.3 Animation елементи example

Example anim01 below demonstrates each of SVG's five animation елементи.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="8cm" height="3cm"  viewBox="0 0 800 300"
     xmlns="http://www.w3.org/2000/svg" version="1.1">
  <desc>Example anim01 - demonstrate animation елементи</desc>
  <rect x="1" y="1" width="798" height="298" 
        fill="none" stroke="blue" stroke-width="2" />
  <!-- The following illustrates the use of the 'animate' елемент
        to animate a rectangles x, y, and width атрибути so that
        the rectangle grows to ultimately fill the viewport. -->
  <rect id="RectElement" x="300" y="100" width="300" height="100"
        fill="rgb(255,255,0)"  >
    <animate атрибутName="x" атрибутType="XML"
             begin="0s" dur="9s" fill="freeze" from="300" to="0" />
    <animate атрибутName="y" атрибутType="XML"
             begin="0s" dur="9s" fill="freeze" from="100" to="0" />
    <animate атрибутName="width" атрибутType="XML"
             begin="0s" dur="9s" fill="freeze" from="300" to="800" />
    <animate атрибутName="height" атрибутType="XML"
             begin="0s" dur="9s" fill="freeze" from="100" to="300" />
  </rect>
  <!-- Set up a new user coordinate system so that
        the text string's origin is at (0,0), allowing
        rotation and scale relative to the new origin -->
  <g transform="translate(100,100)" >
    <!-- The following illustrates the use of the 'set', 'animateMotion',
         'animate' and 'animateTransform' елементи. The 'text' елемент 
         below starts off hidden (i.e., invisible). At 3 seconds, it:
           * becomes visible
           * continuously moves diagonally across the viewport
           * changes color from blue to dark red
           * rotates from -30 to zero degrees
           * scales by a factor of three. -->
    <text id="TextElement" x="0" y="0"
          font-family="Verdana" font-size="35.27" visibility="hidden"  > 
      It's alive!
      <set атрибутName="visibility" атрибутType="CSS" to="visible"
           begin="3s" dur="6s" fill="freeze" />
      <animateMotion path="M 0 0 L 100 100" 
           begin="3s" dur="6s" fill="freeze" />
      <animate атрибутName="fill" атрибутType="CSS"
           from="rgb(0,0,255)" to="rgb(128,0,0)"
           begin="3s" dur="6s" fill="freeze" />
      <animateTransform атрибутName="transform" атрибутType="XML"
           type="rotate" from="-30" to="0"
           begin="3s" dur="6s" fill="freeze" />
      <animateTransform атрибутName="transform" атрибутType="XML"
           type="scale" from="1" to="3" additive="sum"
           begin="3s" dur="6s" fill="freeze" />
    </text>
  </g>
</svg>

Example anim01
At zero seconds		At three seconds
At six seconds		At nine seconds

View this example as SVG (SVG-enabled browsers only)

The sections below describe the various animation атрибути and елементи.

19.2.4 Attributes to identify the target елемент for an animation

The following атрибут is common to all animation елементи and identifies the target елемент for the animation.

Attribute definitions:

xlink:href = "<iri>"

An IRI reference to the елемент which is the target of this animation and which therefore will be modified over time.

The target елемент must be part of the current SVG document fragment.

<iri> must point to exactly one target елемент which is capable of being the target of the given animation. If <iri> points to multiple target елементи, if the given target елемент is not capable of being a target of the given animation, or if the given target елемент is not part of the current SVG document fragment, then the document is in error (see Error processing).

If the ‘xlink:href’ атрибут is not provided, then the target елемент will be the immediate parent елемент of the current animation елемент.

Refer to the descriptions of the individual animation елементи for any restrictions on what types of елементи can be targets of particular types of animations.

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: Specifying the animation target ([SMILANIM], section 3.1).

19.2.5 Attributes to identify the target атрибут or властивість for an animation

The following атрибути are the animation атрибут target атрибути, which identify the target атрибут or властивість for the given target елемент whose value changes over time.

Attribute definitions:

атрибутName = "<атрибутName>"

Specifies the name of the target атрибут. An XMLNS prefix may be used to indicate the XML namespace for the атрибут. The prefix will be interpreted in the scope of the current (i.e., the referencing) animation елемент.

атрибутType = "CSS | XML | auto"

Specifies the namespace in which the target атрибут and its associated values are defined. The атрибут value is one of the following (values are case-sensitive):

CSS: This specifies that the value of ‘атрибутName’ is the name of a CSS властивість defined as animatable in this specification.
XML: This specifies that the value of ‘атрибутName’ is the name of an XML атрибут defined in the default XML namespace for the target елемент. If the value for ‘атрибутName’ has an XMLNS prefix, the implementation must use the associated namespace as defined in the scope of the target елемент. The атрибут must be defined as animatable in this specification.
auto: The implementation should match the ‘атрибутName’ to an атрибут for the target елемент. The implementation must first search through the list of CSS властивості for a matching властивість name, and if none is found, search the default XML namespace for the елемент.

The default value is 'auto'.

19.2.6 Animation with namespaces

Example animns01 below shows a namespace prefix being resolved to a namespace name in the scope of the referencing елемент, and that namespace name being used (regardless of the prefix which happens to be used in the target scope) to identify the атрибут being animated.

<?xml version="1.0" encoding="UTF-8"?>
<svg version="1.1" xmlns="http://www.w3.org/2000/svg"
     xmlns:xlink="http://www.w3.org/1999/xlink">
  <title>Demonstration of the resolution of namespaces for animation</title>
  <!-- at the point of definition, the QName a:href resolves to the namespace
       name "http://www.w3.org/1999/xlink" and the local name "href" -->
  <g xmlns:a="http://www.w3.org/1999/xlink">
    <animate атрибутName="a:href" xlink:href="#foo" dur="2s" to="two.png" fill="freeze"/>
  </g>
  <!-- at the point of use, the namespace name "http://www.w3.org/1999/xlink"
       happens to be bound to the namespace prefix 'b' while the prefix
       'xlink' is bound to a different namespace name -->
  <g xmlns:b="http://www.w3.org/1999/xlink" xmlns:xlink="http://example.net/bar">
    <image xml:id="foo" b:href="one.png" x="35" y="50" width="410" height="160"/>
  </g>
</svg>

View this example as SVG (SVG-enabled browsers only)

19.2.7 Paced animation and complex types

Paced animations assume a notion of distance between the various animation values defined by the ‘to’, ‘from’, ‘by’ and ‘values’ атрибути. Distance is defined only for scalar types (such as <length>), colors and the subset of transformation types that are supported by ‘animateTransform’. In the list of distance functions below, V_a and V_b represent the two values the distance between which is being calculated.

Since paced animation is intended to produce an animation with an even pace of change, it does not make sense to define distance functions for all типи даних. Distance can be usefully defined for types whose values are n-dimensional vectors (including scalars, which are 1-dimensional vectors). For example, a <length> value is a scalar value, and a <color> value is a 3-dimensional vector. Thus атрибути of these types can have paced animation applied to them. On the other hand, a <list-of-length> (as used by ‘stroke-dasharray’) is a list of scalars (1-dimensional vectors), and <list-of-points> (as used by the ‘points’ атрибут on a ‘polygon’) is a list of 2-dimensional vectors. Therefore, these types do not have a distance function defined and cannot have paced animation applied to them.

The distance functions for types that support paced animation are as follows:

<coordinate>, <integer>, <length> and <number>

distance(V_a, V_b) = |V_a − V_b|

Examples: animating the ‘x’ атрибут on a ‘rect’, or the ‘stroke-width’ властивість on a ‘circle’.

<color>

distance(V_a, V_b) = sqrt((V_a.red − V_b.red)² + (V_a.green − V_b.green)² + (V_a.blue − V_b.blue)²), where:

V_i.red is the red component of the V_i color value,

V_i.green is the green component of the V_i color value, and

V_i.blue is the blue component of the V_i color value.

Each of the color component values is usually in the range [0, 1], where 0 represents none of that color component, and 1 represents the maximum amount of that color component, in the sRGB gamut [SRGB]. Since <color> values may specify colors outside of the sRGB gamut, these component values may lie outside the range [0, 1].

Example: animating the ‘fill’ властивість on an ‘ellipse’.

Transform definitions of type 'translate'

distance(V_a, V_b) = sqrt((V_a.tx − V_b.tx)² + (V_a.ty − V_b.ty)²), where:

V_i.tx is the x component of the V_i translation transform value, and

V_i.ty is the y component of the V_i translation transform value.

Example (for all transform definition types): animating the ‘transform’ атрибут on a ‘g’ using ‘animateTransform’.

Transform definitions of type 'scale'

distance(V_a, V_b) = sqrt((V_a.sx − V_b.sx)² + (V_a.sy − V_b.sy)²), where:

V_i.sx is the x component of the V_i scale transform value, and

V_i.sy is the y component of the V_i scale transform value.

Note that, as when specifying scale transformations in a <transform-list>, if the y component of the scale is omitted it is implicitly equal to the x component.

Transform definitions of type 'rotate', 'skewX' and 'skewY'

distance(V_a, V_b) = sqrt((V_a.angle − V_b.angle)²), where:

V_i.angle is the angle component of the V_i rotation or skew transform value.

Since the distance function for rotations is not in terms of the rotation center point components, a paced animation that changes the rotation center point may not appear to have a paced movement when the animation is applied.

Distance functions for all other типи даних are not defined. If calcMode="paced" is used on an animation of an атрибут or властивість whose type is not one of those listed above, the animation effect is undefined. SVG user agents may choose to perform the animation as if calcMode="linear", but this is not required. Authors are recommended not to specify paced animation on types not listed above.

19.2.8 Attributes to control the timing of the animation

The following атрибути are the animation timing атрибути. They are common to all animation елементи and control the timing of the animation, including what causes the animation to start and end, whether the animation runs repeatedly, and whether to retain the end state the animation once the animation ends.

In the syntax specifications that follow, optional white space is indicated as "S", defined as follows:

S ::= (#x20 | #x9 | #xD | #xA)*

Attribute definitions:

begin = "begin-value-list"

Defines when the елемент should begin (i.e. become active).

The атрибут value is a semicolon separated list of values.

begin-value-list ::= begin-value (S? ";" S? begin-value-list )?

A semicolon separated list of begin values. The interpretation of a list of begin times is detailed in SMIL Animation's section on "Evaluation of begin and end time lists".

Describes the елемент begin.

offset-value ::= ( S? "+" | "-" S? )? ( Clock-value )

For SMIL Animation, this describes the елемент begin as an offset from an implicit syncbase. For SVG, the implicit syncbase begin is defined to be relative to the document begin. Negative begin times are entirely valid and easy to compute, as long as there is a resolved document begin time.

syncbase-value ::= ( Id-value "." ( "begin" | "end" ) ) ( S? ("+"|"-") S? Clock-value )?

Describes a syncbase and an optional offset from that syncbase. The елемент begin is defined relative to the begin or active end of another animation. A syncbase consists of an ID reference to another animation елемент followed by either begin or end to identify whether to synchronize with the beginning or active end of the referenced animation елемент.

event-value ::= ( Id-value "." )? ( event-ref ) ( S? ("+"|"-") S? Clock-value )?

Describes an event and an optional offset that determine the елемент begin. The animation begin is defined relative to the time that the event is raised. The list of event-symbols available for a given event-base елемент is the list of event атрибути available for the given елемент as defined by the SVG DTD, with the one difference that the leading 'on' is removed from the event name (i.e., the animation event name is 'click', not 'onclick'). A list of all events supported by SVG can be found in Complete list of supported events. Details of event-based timing are described in SMIL Animation: Unifying Event-based and Scheduled Timing.

repeat-value ::= ( Id-value "." )? "repeat(" integer ")" ( S? ("+"|"-") S? Clock-value )?

Describes a qualified repeat event. The елемент begin is defined relative to the time that the repeat event is raised with the specified iteration value.

accessKey-value ::= "accessKey(" character ")" ( S? ("+"|"-") S? Clock-value )?

Describes an accessKey that determines the елемент begin. The елемент begin is defined relative to the time that the accessKey character is input by the user.

wallclock-sync-value ::= "wallclock(" wallclock-value ")"

Describes the елемент begin as a real-world clock time. The wallclock time syntax is based upon syntax defined in Representation of dates and times [ISO8601].

"indefinite"

The begin of the animation will be determined by a "beginElement()" method call or a hyperlink targeted to the елемент.

The animation DOM methods are described in DOM interfaces.

Hyperlink-based timing is described in SMIL Animation: Hyperlinks and timing.

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'begin' атрибут ([SMILANIM], section 3.2.1).

dur = Clock-value | "media" | "indefinite"

Specifies the simple duration.

The атрибут value can be one of the following:

Clock-value: Specifies the length of the simple duration in presentation time. Value must be greater than 0.
"media": Specifies the simple duration as the intrinsic media duration. This is only valid for елементи that define media.
(For SVG's animation елементи, if 'media' is specified, the атрибут will be ignored.)
"indefinite": Specifies the simple duration as indefinite.

If the animation does not have a ‘dur’ атрибут, the simple duration is indefinite. Note that interpolation will not work if the simple duration is indefinite (although this may still be useful for ‘set’ елементи). Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'dur' атрибут ([SMILANIM], section 3.2.1).

end = "end-value-list"

Defines an end value for the animation that can constrain the active duration. The атрибут value is a semicolon separated list of values.

end-value-list ::= end-value (S? ";" S? end-value-list )?: A semicolon separated list of end values. The interpretation of a list of end times is detailed below.

end-value ::= ( offset-value | syncbase-value | event-value | repeat-value | accessKey-value | wallclock-sync-value | "indefinite" ): Describes the active end of the animation.

A value of 'indefinite' specifies that the end of the animation will be determined by an endElement method call (the animation DOM methods are described in DOM interfaces).

min = Clock-value | "media"

Specifies the minimum value of the active duration.

The атрибут value can be either of the following:

Clock-value

Specifies the length of the minimum value of the active duration, measured in local time.

Value must be greater than 0.

"media"

Specifies the minimum value of the active duration as the intrinsic media duration. This is only valid for елементи that define media. (For SVG's animation елементи, if 'media' is specified, the атрибут will be ignored.)

The default value for ‘min’ is '0'. This does not constrain the active duration at all.

max = Clock-value | "media"

Specifies the maximum value of the active duration.

The атрибут value can be either of the following:

Clock-value

Specifies the length of the maximum value of the active duration, measured in local time.

Value must be greater than 0.

"media"

Specifies the maximum value of the active duration as the intrinsic media duration. This is only valid for елементи that define media. (For SVG's animation елементи, if 'media' is specified, the атрибут will be ignored.)

There is no default value for ‘max’. This does not constrain the active duration at all.

restart = "always" | "whenNotActive" | "never"

always: The animation can be restarted at any time.
This is the default value.
whenNotActive: The animation can only be restarted when it is not active (i.e. after the active end). Attempts to restart the animation during its active duration are ignored.
never: The елемент cannot be restarted for the remainder of the current simple duration of the parent time container. (In the case of SVG, since the parent time container is the SVG document fragment, then the animation cannot be restarted for the remainder of the document duration.)

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'restart' атрибут ([SMILANIM], section 3.3.7).

repeatCount = numeric value | "indefinite"

Specifies the number of iterations of the animation function. It can have the following атрибут values:

numeric value: This is a (base 10) "floating point" numeric value that specifies the number of iterations. It can include partial iterations expressed as fraction values. A fractional value describes a portion of the simple duration. Values must be greater than 0.
"indefinite": The animation is defined to repeat indefinitely (i.e. until the document ends).

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'repeatCount' атрибут ([SMILANIM], section 3.3.1).

repeatDur = Clock-value | "indefinite"

Specifies the total duration for repeat. It can have the following атрибут values:

Clock-value: Specifies the duration in presentation time to repeat the animation function f(t).
"indefinite": The animation is defined to repeat indefinitely (i.e. until the document ends).

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'repeatDur' атрибут ([SMILANIM], section 3.3.1).

fill = "freeze" | "remove"

This атрибут can have the following values:

freeze

The animation effect F(t) is defined to freeze the effect value at the last value of the active duration. The animation effect is "frozen" for the remainder of the document duration (or until the animation is restarted - see SMIL Animation: Restarting animation).

remove

The animation effect is removed (no longer applied) when the active duration of the animation is over. After the active end of the animation, the animation no longer affects the target (unless the animation is restarted - see SMIL Animation: Restarting animation).

This is the default value.

The SMIL Animation specification [SMILANIM] defines the detailed processing rules associated with the above атрибути. Except for any SVG-specific rules explicitly mentioned in this specification, the SMIL Animation specification is the normative definition of the processing rules for the above атрибути.

19.2.8.1 Clock values

Clock values have the same syntax as in SMIL Animation specification [SMILANIM]. The grammar for clock values is repeated here:

Clock-val         ::= Full-clock-val | Partial-clock-val 
                      | Timecount-val
Full-clock-val    ::= Hours ":" Minutes ":" Seconds ("." Fraction)?
Partial-clock-val ::= Minutes ":" Seconds ("." Fraction)?
Timecount-val     ::= Timecount ("." Fraction)? (Metric)?
Metric            ::= "h" | "min" | "s" | "ms"
Hours             ::= DIGIT+; any positive number
Minutes           ::= 2DIGIT; range from 00 to 59
Seconds           ::= 2DIGIT; range from 00 to 59
Fraction          ::= DIGIT+
Timecount         ::= DIGIT+
2DIGIT            ::= DIGIT DIGIT
DIGIT             ::= [0-9]

For Timecount values, the default metric suffix is "s" (for seconds). No embedded white space is allowed in clock values, although leading and trailing white space characters will be ignored.

Clock values describe presentation time.

The following are examples of legal clock values:

Full clock values: 02:30:03 = 2 hours, 30 minutes and 3 seconds
50:00:10.25 = 50 hours, 10 seconds and 250 milliseconds
Partial clock value: 02:33 = 2 minutes and 33 seconds
00:10.5 = 10.5 seconds = 10 seconds and 500 milliseconds
Timecount values:
3.2h    = 3.2 hours = 3 hours and 12 minutes
45min   = 45 minutes
30s     = 30 seconds
5ms     = 5 milliseconds
12.467 = 12 seconds and 467 milliseconds

Fractional values are just (base 10) floating point definitions of seconds. Thus:

00.5s = 500 milliseconds 00:00.005 = 5 milliseconds

19.2.9 Attributes that define animation values over time

The following атрибути are the animation value атрибути. They are common to елементи ‘animate’, ‘animateColor’, ‘animateMotion’ and ‘animateTransform’. These атрибути define the values that are assigned to the target атрибут or властивість over time. The атрибути below provide control over the relative timing of keyframes and the interpolation method between discrete values.

Attribute definitions:

calcMode = "discrete | linear | paced | spline"

Specifies the interpolation mode for the animation. This can take any of the following values. The default mode is 'linear', however if the атрибут does not support linear interpolation (e.g. for strings), the ‘calcMode’ атрибут is ignored and discrete interpolation is used.

discrete: This specifies that the animation function will jump from one value to the next without any interpolation.
linear: Simple linear interpolation between values is used to calculate the animation function. Except for ‘animateMotion’, this is the default ‘calcMode’.
paced: Defines interpolation to produce an even pace of change across the animation. This is only supported for the типи даних for which there is an appropriate distance function defined, which includes only scalar numeric types plus the types listed in Paced animation and complex types. If 'paced' is specified, any ‘keyTimes’ or ‘keySplines’ will be ignored. For ‘animateMotion’, this is the default ‘calcMode’. Authors are discouraged from using paced animation on types that do not have a distance function defined, due to its unpredictable behavior in some user agents.
spline: Interpolates from one value in the ‘values’ list to the next according to a time function defined by a cubic Bézier spline. The points of the spline are defined in the ‘keyTimes’ атрибут, and the control points for each interval are defined in the ‘keySplines’ атрибут.

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'calcMode' атрибут ([SMILANIM], section 3.2.3).

values = "<list>"

A semicolon-separated list of one or more values. Vector-valued атрибути are supported using the vector syntax of the ‘атрибутType’ domain. Per the SMIL specification, leading and trailing white space, and white space before and after semicolon separators, is allowed and will be ignored. Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'values' атрибут ([SMILANIM], section 3.2.2).

keyTimes = "<list>"

A semicolon-separated list of time values used to control the pacing of the animation. Each time in the list corresponds to a value in the ‘values’ атрибут list, and defines when the value is used in the animation function. Each time value in the ‘keyTimes’ list is specified as a floating point value between 0 and 1 (inclusive), representing a proportional offset into the simple duration of the animation елемент.

For animations specified with a ‘values’ list, the ‘keyTimes’ атрибут if specified must have exactly as many values as there are in the ‘values’ атрибут. For from/to/by animations, the ‘keyTimes’ атрибут if specified must have two values.

Each successive time value must be greater than or equal to the preceding time value.

The ‘keyTimes’ list semantics depends upon the interpolation mode:

For linear and spline animation, the first time value in the list must be 0, and the last time value in the list must be 1. The key time associated with each value defines when the value is set; values are interpolated between the key times.
For discrete animation, the first time value in the list must be 0. The time associated with each value defines when the value is set; the animation function uses that value until the next time defined in ‘keyTimes’.

If the interpolation mode is 'paced', the ‘keyTimes’ атрибут is ignored.

If there are any errors in the ‘keyTimes’ specification (bad values, too many or too few values), the document fragment is in error (see error processing).

If the simple duration is indefinite, any ‘keyTimes’ specification will be ignored.

Because paced animation interpolation is unspecified for some value types, authors are encouraged to use 'linear' animation interpolation with calculated ‘keyTimes’ to achieve particular interpolation behavior for these types.

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'keyTimes' атрибут ([SMILANIM], section 3.2.3).

keySplines = "<list>"

A set of Bézier control points associated with the ‘keyTimes’ list, defining a cubic Bézier function that controls interval pacing. The атрибут value is a semicolon-separated list of control point descriptions. Each control point description is a set of four values: x1 y1 x2 y2, describing the Bézier control points for one time segment. Note: SMIL allows these values to be separated either by commas with optional whitespace, or by whitespace alone. The ‘keyTimes’ values that define the associated segment are the Bézier "anchor points", and the ‘keySplines’ values are the control points. Thus, there must be one fewer sets of control points than there are ‘keyTimes’.

The values must all be in the range 0 to 1.

This атрибут is ignored unless the ‘calcMode’ is set to 'spline'.

If there are any errors in the ‘keySplines’ specification (bad values, too many or too few values), the document fragment is in error (see error processing).

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'keySplines' атрибут ([SMILANIM], section 3.2.3).

from = "<value>"

Specifies the starting value of the animation.
Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'from' атрибут ([SMILANIM], section 3.2.2).

to = "<value>"

Specifies the ending value of the animation.
Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'to' атрибут ([SMILANIM], section 3.2.2).

by = "<value>"

Specifies a relative offset value for the animation.
Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'by' атрибут ([SMILANIM], section 3.2.2).

The animation values specified in the animation елемент must be legal values for the specified атрибут. Leading and trailing white space, and white space before and after semicolon separators, will be ignored.

All values specified must be legal values for the specified атрибут (as defined in the associated namespace). If any values are not legal, the document fragment is in error (see error processing).

If a list of values is used, the animation will apply the values in order over the course of the animation. If a list of ‘values’ is specified, any ‘from’, ‘to’ and ‘by’ атрибут values are ignored.

The processing rules for the variants of from/by/to animations are described in Animation function values with the following exception.

In order to provide behavior that is intuitive and consistent between discrete animations with an explicitly specified ‘from’ атрибут (e.g. "from-to animation") and those where the underlying value is used (e.g. "to animation"), the behavior of discrete to-animation in SVG deviates from the definition in SMIL Animation. As with a discrete from-to animation, a discrete to animation will set the underlying value for the first half of the simple duration (or, if a ‘keyTimes’ list is provided, until the simple duration specified by the second value in the ‘keyTimes’ list) and the ‘to’ value for the remainder of the simple duration.

The following figure illustrates the interpretation of the ‘keySplines’ атрибут. Each diagram illustrates the effect of ‘keySplines’ settings for a single interval (i.e. between the associated pairs of values in the ‘keyTimes’ and ‘values’ lists.). The horizontal axis can be thought of as the input value for the unit progress of interpolation within the interval - i.e. the pace with which interpolation proceeds along the given interval. The vertical axis is the resulting value for the unit progress, yielded by the function that the ‘keySplines’ атрибут defines. Another way of describing this is that the horizontal axis is the input unit time for the interval, and the vertical axis is the output unit time. See also the section Timing and real-world clock times.

Examples of keySplines
	keySplines="0 0 1 1" (the default)		keySplines=".5 0 .5 1"
	keySplines="0 .75 .25 1"		keySplines="1 0 .25 .25"

To illustrate the calculations, consider the simple example:

<animate dur="4s" values="10; 20" keyTimes="0; 1"
     calcMode="spline" keySplines={as in table} />

Using the ‘keySplines’ values for each of the four cases above, the approximate interpolated values as the animation proceeds are:

Value of ‘keySplines’	Initial value	After 1s	After 2s	After 3s	Final value
0 0 1 1	10.0	12.5	15.0	17.5	20.0
.5 0 .5 1	10.0	11.0	15.0	19.0	20.0
0 .75 .25 1	10.0	18.0	19.3	19.8	20.0
1 0 .25 .25	10.0	10.1	10.6	16.9	20.0

For a formal definition of Bézier spline calculation, see [FOLEY-VANDAM], pp. 488-491.

19.2.10 Attributes that control whether animations are additive

It is frequently useful to define animation as an offset or delta to an атрибут's value, rather than as absolute values. A simple "grow" animation can increase the width of an object by 10 pixels:

<rect width="20px" ...>
  <animate атрибутName="width" from="0px" to="10px" dur="10s"
           additive="sum"/>
</rect>

It is frequently useful for repeated animations to build upon the previous results, accumulating with each interation. The following example causes the rectangle to continue to grow with each repeat of the animation:

<rect width="20px" ...>
  <animate атрибутName="width" from="0px" to="10px" dur="10s"
           additive="sum" accumulate="sum" repeatCount="5"/>
</rect>

At the end of the first repetition, the rectangle has a width of 30 pixels. At the end of the second repetition, the rectangle has a width of 40 pixels. At the end of the fifth repetition, the rectangle has a width of 70 pixels.

For more information about additive animations, see SMIL Animation: Additive animation. For more information on cumulative animations, see SMIL Animation: Controlling behavior of repeating animation - Cumulative animation.

The following атрибути are the animation addition атрибути, which are common to елементи ‘animate’, ‘animateColor’, ‘animateMotion’ and ‘animateTransform’.

Attribute definitions:

additive = "replace | sum"

Controls whether or not the animation is additive.

sum: Specifies that the animation will add to the underlying value of the атрибут and other lower priority animations.
replace: Specifies that the animation will override the underlying value of the атрибут and other lower priority animations. This is the default, however the behavior is also affected by the animation value атрибути ‘by’ and ‘to’, as described in SMIL Animation: Як from, to and by атрибути affect additive behavior.

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'additive' атрибут ([SMILANIM], section 3.3.6).

accumulate = "none | sum"

Controls whether or not the animation is cumulative.

sum: Specifies that each repeat iteration after the first builds upon the last value of the previous iteration.
none: Specifies that repeat iterations are not cumulative. This is the default.

This атрибут is ignored if the target атрибут value does not support addition, or if the animation елемент does not repeat.

Cumulative animation is not defined for "to animation".

This атрибут will be ignored if the animation function is specified with only the ‘to’ атрибут.

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this атрибут is the SMIL Animation specification. In particular, see SMIL Animation: 'accumulate' атрибут ([SMILANIM], section 3.3.1).

19.2.11 Inheritance

SVG allows both атрибути and властивості to be animated. If a given атрибут or властивість is inheritable by descendants, then animations on a parent елемент such as a ‘g’ елемент has the effect of propagating the атрибут or властивість animation values to descendant елементи as the animation proceeds; thus, descendant елементи can inherit animated атрибути and властивості from their ancestors.

19.2.12 The ‘animate’ елемент

The ‘animate’ елемент is used to animate a single атрибут or властивість over time. For example, to make a rectangle repeatedly fade away over 5 seconds, you can specify:

<rect>
  <animate атрибутType="CSS" атрибутName="opacity" 
         from="1" to="0" dur="5s" repeatCount="indefinite" />
</rect>

Except for any SVG-specific rules explicitly mentioned in this specification, the normative definition for this елемент is the SMIL Animation specification. In particular, see SMIL Animation: 'animate' елемент ([SMILANIM], section 4.1).

‘animate’

Categories:

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
animation event атрибути — ‘onbegin’, ‘onend’, ‘onrepeat’, ‘onload’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
animation атрибут target атрибути — ‘атрибутType’, ‘атрибутName’
animation timing атрибути — ‘begin’, ‘dur’, ‘end’, ‘min’, ‘max’, ‘restart’, ‘repeatCount’, ‘repeatDur’, ‘fill’
animation value атрибути — ‘calcMode’, ‘values’, ‘keyTimes’, ‘keySplines’, ‘from’, ‘to’, ‘by’
animation addition атрибути — ‘additive’, ‘accumulate’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘externalResourcesRequired’

DOM Інтерфейсs:

SVGAnimateElement

The ‘color-interpolation’ властивість applies to color interpolations that result from animations using the ‘animate’ елемент.

For a list of атрибути and властивості that can be animated using the ‘animate’ елемент, see Elements, атрибути and властивості that can be animated.

19.2.13 The ‘set’ елемент

The ‘set’ елемент provides a simple means of just setting the value of an атрибут for a specified duration. It supports all атрибут types, including those that cannot reasonably be interpolated, such as string and boolean values. The ‘set’ елемент is non-additive. The additive and accumulate атрибути are not allowed, and will be ignored if specified.

‘set’

Categories:

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
animation event атрибути — ‘onbegin’, ‘onend’, ‘onrepeat’, ‘onload’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
animation атрибут target атрибути — ‘атрибутType’, ‘атрибутName’
animation timing атрибути — ‘begin’, ‘dur’, ‘end’, ‘min’, ‘max’, ‘restart’, ‘repeatCount’, ‘repeatDur’, ‘fill’
‘externalResourcesRequired’
‘to’

DOM Інтерфейсs:

SVGSetElement

Attribute definitions:

to = "<value>": Specifies the value for the атрибут during the duration of the ‘set’ елемент. The argument value must match the атрибут type.

For a list of атрибути and властивості that can be animated using the ‘set’ елемент, see Elements, атрибути and властивості that can be animated.

19.2.14 The ‘animateMotion’ елемент

The ‘animateMotion’ елемент causes a referenced елемент to move along a motion path.

‘animateMotion’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of descriptive елементи and at most one ‘mpath’ елемент, in any order.

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
animation event атрибути — ‘onbegin’, ‘onend’, ‘onrepeat’, ‘onload’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
animation timing атрибути — ‘begin’, ‘dur’, ‘end’, ‘min’, ‘max’, ‘restart’, ‘repeatCount’, ‘repeatDur’, ‘fill’
animation value атрибути — ‘calcMode’, ‘values’, ‘keyTimes’, ‘keySplines’, ‘from’, ‘to’, ‘by’
animation addition атрибути — ‘additive’, ‘accumulate’
‘externalResourcesRequired’
‘path’
‘keyPoints’
‘rotate’
‘origin’

DOM Інтерфейсs:

SVGAnimateMotionElement

Attribute definitions:

calcMode = "discrete | linear | paced | spline"

Specifies the interpolation mode for the animation. Refer to general description of the ‘calcMode’ атрибут above. The only difference is that the default value for the ‘calcMode’ for ‘animateMotion’ is 'paced'. See SMIL Animation: 'calcMode' атрибут for 'animateMotion'.

path = "<path-data>"

The motion path, expressed in the same format and interpreted the same way as the ‘d’ атрибут on the ‘path’ елемент. The effect of a motion path animation is to add a supplemental transformation matrix onto the CTM for the referenced object which causes a translation along the x- and y-axes of the current user coordinate system by the computed X and Y values computed over time.

keyPoints = "<list-of-numbers>"

‘keyPoints’ takes a semicolon-separated list of floating point values between 0 and 1 and indicates how far along the motion path the object shall move at the moment in time specified by corresponding ‘keyTimes’ value. Distance calculations use the user agent's distance along the path algorithm. Each progress value in the list corresponds to a value in the ‘keyTimes’ атрибут list.

If a list of ‘keyPoints’ is specified, there must be exactly as many values in the ‘keyPoints’ list as in the ‘keyTimes’ list.

If there are any errors in the ‘keyPoints’ specification (bad values, too many or too few values), then the document is in error (see Error processing).

rotate = "<number> | auto | auto-reverse"

The ‘rotate’ атрибут post-multiplies a supplemental transformation matrix onto the CTM of the target елемент to apply a rotation transformation about the origin of the current user coordinate system. The rotation transformation is applied after the supplemental translation transformation that is computed due to the ‘path’ атрибут.

auto: Indicates that the object is rotated over time by the angle of the direction (i.e., directional tangent vector) of the motion path.
auto-reverse: Indicates that the object is rotated over time by the angle of the direction (i.e., directional tangent vector) of the motion path plus 180 degrees.
<number>: Indicates that the target елемент has a constant rotation transformation applied to it, where the rotation angle is the specified number of degrees.

The default value is '0'.

origin = "default"

The ‘origin’ атрибут is defined in the SMIL Animation specification ([SMILANIM], section 4.3). It has no effect in SVG.

‘mpath’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
‘externalResourcesRequired’
‘xlink:href’

DOM Інтерфейсs:

SVGMPathElement

Attribute definitions:

xlink:href = "<iri>": An IRI reference to the ‘path’ елемент which defines the motion path.
Animatable: no.

For ‘animateMotion’, the specified values for ‘from’, ‘by’, ‘to’ and ‘values’ consists of x, y coordinate pairs, with a single comma and/or white space separating the x coordinate from the y coordinate. For example, from="33,15" specifies an x coordinate value of 33 and a y coordinate value of 15.

If provided, the ‘values’ атрибут must consists of a list of x, y coordinate pairs. Coordinate values are separated by at least one white space character or a comma. Additional white space around the separator is allowed. For example, values="10,20;30,20;30,40" or values="10mm,20mm;30mm,20mm;30mm,40mm". Each coordinate represents a length. Attributes ‘from’, ‘by’, ‘to’ and ‘values’ specify a shape on the current canvas which represents the motion path.

Two options are available which allow definition of a motion path using any of SVG's path data commands:

the ‘path’ атрибут defines a motion path directly on ‘animateMotion’ елемент using any of SVG's path data commands.
the ‘mpath’ sub-елемент provides the ability to reference an external ‘path’ елемент as the definition of the motion path.

Note that SVG's path data commands can only contain values in user space, whereas ‘from’, ‘by’, ‘to’ and ‘values’ can specify coordinates in user space or using unit identifiers. See Units.

The various (x,y) points of the shape provide a supplemental transformation matrix onto the CTM for the referenced object which causes a translation along the x- and y-axes of the current user coordinate system by the (x,y) values of the shape computed over time. Thus, the referenced object is translated over time by the offset of the motion path relative to the origin of the current user coordinate system. The supplemental transformation is applied on top of any transformations due to the target елемент's ‘transform’ атрибут or any animations on that атрибут due to ‘animateTransform’ елементи on the target елемент.

The ‘additive’ and ‘accumulate’ атрибути apply to ‘animateMotion’ елементи. Multiple ‘animateMotion’ елементи all simultaneously referencing the same target елемент can be additive with respect to each other; however, the transformations which result from the ‘animateMotion’ елементи are always supplemental to any transformations due to the target елемент's ‘transform’ атрибут or any ‘animateTransform’ елементи.

The default calculation mode (‘calcMode’) for ‘animateMotion’ is "paced". This will produce constant velocity motion along the specified path. Note that while animateMotion елементи can be additive, it is important to observe that the addition of two or more "paced" (constant velocity) animations might not result in a combined motion animation with constant velocity.

When a path is combined with "discrete", "linear" or "spline" ‘calcMode’ settings, and if атрибут ‘keyPoints’ is not provided, the number of values is defined to be the number of points defined by the path, unless there are "move to" commands within the path. A "move to" command within the path (i.e. other than at the beginning of the path description) A "move to" command does not count as an additional point when dividing up the duration, or when associating ‘keyTimes’, ‘keySplines’ and ‘keyPoints’ values. When a path is combined with a "paced" ‘calcMode’ setting, all "move to" commands are considered to have 0 length (i.e. they always happen instantaneously), and is not considered in computing the pacing.

For more flexibility in controlling the velocity along the motion path, the ‘keyPoints’ атрибут provides the ability to specify the progress along the motion path for each of the ‘keyTimes’ specified values. If specified, ‘keyPoints’ causes ‘keyTimes’ to apply to the values in ‘keyPoints’ rather than the points specified in the ‘values’ атрибут array or the points on the ‘path’ атрибут.

The override rules for ‘animateMotion’ are as follows. Regarding the definition of the motion path, the ‘mpath’ елемент overrides the the ‘path’ атрибут, which overrides ‘values’, which overrides ‘from’, ‘by’ and ‘to’. Regarding determining the points which correspond to the ‘keyTimes’ атрибути, the ‘keyPoints’ атрибут overrides ‘path’, which overrides ‘values’, which overrides ‘from’, ‘by’ and ‘to’.

At any time t within a motion path animation of duration dur, the computed coordinate (x,y) along the motion path is determined by finding the point (x,y) which is t/dur distance along the motion path using the user agent's distance along the path algorithm.

The following example demonstrates the supplemental transformation matrices that are computed during a motion path animation.

Example animMotion01 shows a triangle moving along a motion path.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="5cm" height="3cm"  viewBox="0 0 500 300"
     xmlns="http://www.w3.org/2000/svg" version="1.1"
     xmlns:xlink="http://www.w3.org/1999/xlink" >
  <desc>Example animMotion01 - demonstrate motion animation computations</desc>
  <rect x="1" y="1" width="498" height="298"
        fill="none" stroke="blue" stroke-width="2" />
  <!-- Draw the outline of the motion path in blue, along
          with three small circles at the start, middle and end. -->
  <path id="path1" d="M100,250 C 100,50 400,50 400,250"
        fill="none" stroke="blue" stroke-width="7.06"  />
  <circle cx="100" cy="250" r="17.64" fill="blue"  />
  <circle cx="250" cy="100" r="17.64" fill="blue"  />
  <circle cx="400" cy="250" r="17.64" fill="blue"  />
  <!-- Here is a triangle which will be moved about the motion path.
       It is defined with an upright orientation with the base of
       the triangle centered horizontally just above the origin. -->
  <path d="M-25,-12.5 L25,-12.5 L 0,-87.5 z"
        fill="yellow" stroke="red" stroke-width="7.06"  >
    <!-- Define the motion path animation -->
    <animateMotion dur="6s" repeatCount="indefinite" rotate="auto" >
       <mpath xlink:href="#path1"/>
    </animateMotion>
  </path>
</svg>

Example animMotion01
At zero seconds		At three seconds		At six seconds

The following table shows the supplemental transformation matrices that are applied to achieve the effect of the motion path animation.

	After 0s	After 3s	After 6s
Supplemental transform due to movement along motion path	translate(100,250)	translate(250,100)	translate(400,250)
Supplemental transform due to rotate="auto"	rotate(-90)	rotate(0)	rotate(90)

For a list of елементи that can be animated using the ‘animateMotion’ елемент, see Elements, атрибути and властивості that can be animated.

19.2.15 The ‘animateColor’ елемент

The ‘animateColor’ елемент specifies a color transformation over time.

‘animateColor’

Categories:

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
animation event атрибути — ‘onbegin’, ‘onend’, ‘onrepeat’, ‘onload’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
animation атрибут target атрибути — ‘атрибутType’, ‘атрибутName’
animation timing атрибути — ‘begin’, ‘dur’, ‘end’, ‘min’, ‘max’, ‘restart’, ‘repeatCount’, ‘repeatDur’, ‘fill’
animation value атрибути — ‘calcMode’, ‘values’, ‘keyTimes’, ‘keySplines’, ‘from’, ‘to’, ‘by’
animation addition атрибути — ‘additive’, ‘accumulate’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘externalResourcesRequired’

DOM Інтерфейсs:

SVGAnimateColorElement

The ‘from’, ‘by’ and ‘to’ атрибути take color values, where each color value is expressed using the following syntax (the same syntax as used in SVG's властивості that can take color values):

<color> <icccolor>?

The ‘values’ атрибут for the ‘animateColor’ елемент consists of a semicolon-separated list of color values, with each color value expressed in the above syntax.

Out of range color values can be provided, but user agent processing will be implementation dependent. User agents should clamp color values to allow color range values as late as possible, but note that system differences might preclude consistent behavior across different systems.

The ‘color-interpolation’ властивість applies to color interpolations that result from ‘animateColor’ animations.

The use of ‘animateColor’ is deprecated, since all of its functionality can be achieved simply by using ‘animate’ to target властивості that can take color values. The ‘animateColor’ елемент may be dropped from a future version of the SVG specification.

For a list of атрибути and властивості that can be animated using the ‘animateColor’ елемент, see Elements, атрибути and властивості that can be animated.

19.2.16 The ‘animateTransform’ елемент

The ‘animateTransform’ елемент animates a transformation атрибут on a target елемент, thereby allowing animations to control translation, scaling, rotation and/or skewing.

‘animateTransform’

Categories:

View this example as SVG (SVG-enabled browsers only)

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’

Attributes:

conditional processing атрибути — ‘requiredFeatures’, ‘requiredExtensions’, ‘systemLanguage’
core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
animation event атрибути — ‘onbegin’, ‘onend’, ‘onrepeat’, ‘onload’
xlink атрибути — ‘xlink:href’, ‘xlink:show’, ‘xlink:actuate’, ‘xlink:type’, ‘xlink:role’, ‘xlink:arcrole’, ‘xlink:title’
animation атрибут target атрибути — ‘атрибутType’, ‘атрибутName’
animation timing атрибути — ‘begin’, ‘dur’, ‘end’, ‘min’, ‘max’, ‘restart’, ‘repeatCount’, ‘repeatDur’, ‘fill’
animation value атрибути — ‘calcMode’, ‘values’, ‘keyTimes’, ‘keySplines’, ‘from’, ‘to’, ‘by’
animation addition атрибути — ‘additive’, ‘accumulate’
‘externalResourcesRequired’
‘type’

DOM Інтерфейсs:

SVGAnimateTransformElement

Attribute definitions:

type = "translate | scale | rotate | skewX | skewY": Indicates the type of transformation which is to have its values change over time. If the атрибут is not specified, then the effect is as if a value of 'translate' were specified.

The ‘from’, ‘by’ and ‘to’ атрибути take a value expressed using the same syntax that is available for the given transformation type:

For a type="translate", each individual value is expressed as <tx> [,<ty>].
For a type="scale", each individual value is expressed as <sx> [,<sy>].
For a type="rotate", each individual value is expressed as <rotate-angle> [<cx> <cy>].
For a type="skewX" and type="skewY", each individual value is expressed as <skew-angle>.

(See The ‘transform’ атрибут.)

The ‘values’ атрибут for the ‘animateTransform’ елемент consists of a semicolon-separated list of values, where each individual value is expressed as described above for ‘from’, ‘by’ and ‘to’.

The animation effect for ‘animateTransform’ is post-multiplied to the underlying value for additive ‘animateTransform’ animations (see below) instead of added to the underlying value, due to the specific behavior of ‘animateTransform’.

From-to, from-by and by animations are defined in SMIL to be equivalent to a corresponding values animation. See the Animation function values section of SMIL Animation ([SMILANIM], section 3.2.2). Якever, to animations are a mixture of additive and non-additive behavior, as described in the Як from, to and by атрибути affect additive behavior section of SMIL Animation ([SMILANIM], section 3.3.6). To animations provide specific functionality to get a smooth change from the underlying value to the ‘to’ атрибут value, which conflicts mathematically with the requirement for additive transform animations to be post-multiplied. As a consequence, in SVG 1.1 the behavior of to animations for ‘animateTransform’ is undefined. Authors are suggested to use from-to, from-by, by or values animations to achieve any desired transform animation.

If ‘calcMode’ has the value 'paced', then the "distance" for the transformation is calculated as further described in Paced animations and complex types.

When an animation is active, the effect of non-additive ‘animateTransform’ (i.e., additive="replace") is to replace the given атрибут's value with the transformation defined by the ‘animateTransform’. The effect of additive (i.e., additive="sum") is to post-multiply the transformation matrix corresponding to the transformation defined by this ‘animateTransform’. To illustrate:

<rect transform="skewX(30)"...>
  <animateTransform атрибутName="transform" атрибутType="XML"
                    type="rotate" from="0" to="90" dur="5s"
                    additive="replace" fill="freeze"/>
  <animateTransform атрибутName="transform" атрибутType="XML"
                    type="scale" from="1" to="2" dur="5s"
                    additive="replace" fill="freeze"/>
</rect>

In the code snippet above, because the both animations have additive="replace", the first animation overrides the transformation on the rectangle itself and the second animation overrides the transformation from the first animation; therefore, at time 5 seconds, the visual result of the above two animations would be equivalent to the following static rectangle:

<rect transform="scale(2)" ... />

whereas in the following example:

<rect transform="skewX(30)"...>
  <animateTransform атрибутName="transform" атрибутType="XML"
                    type="rotate" from="0" to="90" dur="5s" 
                    additive="sum" fill="freeze"/>
  <animateTransform атрибутName="transform" атрибутType="XML"
                    type="scale" from="1" to="2" dur="5s"
                    additive="sum" fill="freeze"/>
</rect>

In this code snippet, because the both animations have additive="sum", the first animation post-multiplies its transformation to any transformations on the rectangle itself and the second animation post-multiplies its transformation to any transformation from the first animation; therefore, at time 5 seconds, the visual result of the above two animations would be equivalent to the following static rectangle:

<rect transform="skewX(30) rotate(90) scale(2)" ... />

Note that the zero value used when performing a by animation with type="scale" is indeed 0. Thus, performing the following animation causes the rectangle to be invisible at time 0s (since the animated transform list value is 'scale(0)'), and be scaled back to its original size at time 5s (since the animated transform list value is 'scale(1)'):

<rect width="100" height="100">
  <animateTransform атрибутName="transform" атрибутType="XML"
                    type="scale" by="1" dur="5s" fill="freeze"/>
</rect>

When a transform animation has accumulate='sum', the accumulation that occurs for each completed repetition of the animation is computed on the values specified in the ‘animateTransform’ елемент's animation value атрибути (i.e., ‘values’, ‘from’, ‘to’ and ‘by’) and not on the transformation matrix that these values represent. For example, in the following code snippet, 3 is added to the scale value at the start of each repetition:

<rect width="100" height="100">
  <animateTransform атрибутName="transform" атрибутType="XML"
                    type="scale" from="2" to="3" repeatCount="3" dur="4s"
                    fill="freeze"/>
</rect>

The following graph and table shows the animated ‘transform’ value on the ‘rect’ over the course of the animation:

The scale value animates from 2 to 12 with discontinuities at 4s and 8s.

Time	Value
0s	scale(2)
1s	scale(2.25)
2s	scale(2.5)
3s	scale(2.75)
4s	scale(5)
5s	scale(5.25)
6s	scale(5.5)
7s	scale(5.75)
8s	scale(8)
9s	scale(8.25)
10s	scale(8.5)
11s	scale(8.75)
12s	scale(9)

Transform item types that can have multiple values – 'translate', 'scale' and 'rotate' – are treated as vectors and accumulation is performed with vector addition. Optional values that are omitted are taken to have their usual implied value: 1 for the <sy> component of a 'scale' and 0 for the <tx> component of a 'translate' and the <cx cy> components of a 'rotate'.

For example, consider the following code snippet, which has a cumulative transform animation of type 'rotate':

<rect width="100" height="100">
  <animateTransform атрибутName="transform" атрибутType="XML"
                    type="rotate" from="0 30 40" to="10 30 40"
                    repeatCount="2" dur="1s" fill="freeze"/>
</rect>

At time 1 second, the animated value of ‘transform’ on the ‘rect’ will jump from 'rotate(10 30 40)' to 'rotate(10 60 80)', because the effect of the accumulation is to take the value at the end of the first repetition, '10 30 40', and add to it the value at simple duration t = 0s, which is '0 30 40'.

For a list of атрибути and властивості that can be animated using the ‘animateTransform’ елемент, see Elements, атрибути and властивості that can be animated.

19.2.17 Elements, атрибути and властивості that can be animated

The following lists all of the елементи which can be animated by an ‘animateMotion’ елемент:

‘svg’
‘g’
‘defs’
‘use’
‘image’
‘switch’
‘path’
‘rect’
‘circle’
‘ellipse’
‘line’
‘polyline’
‘polygon’
‘text’
‘clipPath’
‘mask’
‘a’
‘foreignObject’

Each атрибут or властивість within this specification indicates whether or not it can be animated by SVG's animation елементи. Animatable атрибути and властивості are designated as follows:

Animatable: yes.

whereas атрибути and властивості that cannot be animated are designated:

Animatable: no.

Some властивості are defined as being animatable but only for non-additive animations:

Animatable: yes (non-additive).

SVG has a defined set of basic типи даних for its various supported атрибути and властивості. For those атрибути and властивості that can be animated, the following table indicates which animation елементи can be used to animate each of the basic типи даних. If a given атрибут or властивість can take values of keywords (which are not additive) or numeric values (which are additive), then additive animations are possible if the subsequent animation uses a numeric value even if the base animation uses a keyword value; however, if the subsequent animation uses a keyword value, additive animation is not possible.

Data type	Additive?	‘animate’	‘set’	‘animateColor’	‘animateTransform’	Notes
<angle>	yes	yes	yes	no	no
<color>	yes	yes	yes	yes	no	Only additive if each value can be converted to an RGB color.
<coordinate>	yes	yes	yes	no	no
<frequency>	no	no	no	no	no
<integer>	yes	yes	yes	no	no
<length>	yes	yes	yes	no	no
<list-of-`T`s>	no	yes	yes	no	no
<number>	yes	yes	yes	no	no
<paint>	yes	yes	yes	yes	no	Only additive if each value can be converted to an RGB color.
<percentage>	yes	yes	yes	no	no
<time>	no	no	no	no	no
<transform-list>	yes	no	no	no	yes	Additive means that a transformation is post-multiplied to the base set of transformations.
<iri>	no	yes	yes	no	no
All other типи даних used in animatable атрибути and властивості	no	yes	yes	no	no

Any deviation from the above table or other special note about the animation capabilities of a particular атрибут or властивість is included in the section of the specification where the given атрибут or властивість is defined.

19.3 Animation using the SVG DOM

Example dom01 shows a simple animation using the DOM.

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" 
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="4cm" height="2cm" viewBox="0 0 400 200"
     xmlns="http://www.w3.org/2000/svg"
     onload="StartAnimation(evt)" version="1.1">
  <script type="application/ecmascript"><![CDATA[
    var timevalue = 0;
    var timer_increment = 50;
    var max_time = 5000;
    var text_елемент;
    function StartAnimation(evt) {
      text_елемент = evt.target.ownerDocument.getElementById("TextElement");
      ShowAndGrowElement();
    }
    function ShowAndGrowElement() {
      timevalue = timevalue + timer_increment;
      if (timevalue > max_time)
        return;
      // Scale the text string gradually until it is 20 times larger
      scalefactor = (timevalue * 20.) / max_time;
      text_елемент.setAttribute("transform", "scale(" + scalefactor + ")");
      // Make the string more opaque
      opacityfactor = timevalue / max_time;
      text_елемент.setAttribute("opacity", opacityfactor);
      // Call ShowAndGrowElement again <timer_increment> milliseconds later.
      setTimeout("ShowAndGrowElement()", timer_increment)
    }
    window.ShowAndGrowElement = ShowAndGrowElement
  ]]></script>
  <rect x="1" y="1" width="398" height="198"
        fill="none" stroke="blue" stroke-width="2"/>
  <g transform="translate(50,150)" fill="red" font-size="7">
    <text id="TextElement">SVG</text>
  </g>
</svg>

Example dom01
At zero seconds		At 2.5 seconds		At five seconds

The above SVG file contains a single graphics елемент, a text string that says "SVG". The animation loops for 5 seconds. The text string starts out small and transparent and grows to be large and opaque. Here is an explanation of how this example works:

The onload="StartAnimation(evt)" атрибут indicates that, once the document has been fully loaded and processed, invoke ECMAScript function StartAnimation.
The ‘script’ елемент defines the ECMAScript which makes the animation happen. The StartAnimation() function is only called once to give a value to global variable text_елемент and to make the initial call to ShowAndGrowElement(). ShowAndGrowElement() is called every 50 milliseconds and resets the ‘transform’ and ‘style’ атрибути on the text елемент to new values each time it is called. At the end of ShowAndGrowElement, the function tells the ECMAScript engine to call itself again after 50 more milliseconds.
The ‘g’ елемент shifts the coordinate system so that the origin is shifted toward the lower-left of the viewing area. It also defines the fill color and font-size to use when drawing the text string.
The ‘text’ елемент contains the text string and is the елемент whose атрибути get changed during the animation.

If scripts are modifying the same атрибути or властивості that are being animated by SVG's animation елементи, the scripts modify the base value for the animation. If a base value is modified while an animation елемент is animating the corresponding атрибут or властивість, the animations are required to adjust dynamically to the new base value.

If a script is modifying a властивість on the override style sheet at the same time that an animation елемент is animating that властивість, the result is implementation-dependent; thus, it is recommended that this be avoided.

19.4 DOM interfaces

Below are the DOM interfaces for the елементи defined in this chapter. In addition, ElementTimeControl and TimeEvent, which are from SMIL Animation, are included here for easy reference.

19.4.1 Інтерфейс ElementTimeControl

SMIL Animation supports several methods for controlling the behavior of animation: beginElement(), beginElementAt(), endElement() and endElementAt(). These methods are used to begin and end the active duration of an елемент. Authors can (but are not required to) declare the timing to respond to the DOM using the following syntax:

<animate begin="indefinite" end="indefinite" .../>

If a DOM method call is made to begin or end the елемент (using beginElement(), beginElementAt(), endElement() or endElementAt()), each method call creates a single instance time (in the appropriate instance times list). These times are then interpreted as part of the semantics of lists of times, as described in Evaluation of begin and end time lists.

The instance time associated with a beginElement() or endElement() call is the current presentation time at the time of the DOM method call.
The instance time associated with a beginElementAt() or endElementAt() call is the current presentation time at the time of the DOM method call, plus or minus the specified offset.
Note that beginElement() is subject to the ‘restart’ атрибут in the same manner that event-based begin timing is. Refer also to SMIL Animation: Restarting animation ([SMILANIM], section 3.3.7).

The expectation of the following interface is that an instance of the ElementTimeControl interface can be obtained by using binding-specific casting methods on an instance of an animation елемент. A DOM application can use the hasFeature method of the DOMImplementation interface to determine whether the ElementTimeControl interface is supported or not. The feature string for this interface is "TimeControl".

interface ElementTimeControl {
  void beginElement();
  void beginElementAt(in float offset);
  void endElement();
  void endElementAt(in float offset);
};

Operations:

void beginElement()

Creates a begin instance time for the current time. The new instance time is added to the begin instance times list. The behavior of this method is equivalent to beginElementAt(0).

void beginElementAt(in float offset)

Creates a begin instance time for the current time plus the specified offset. The new instance time is added to the begin instance times list.

Parameters

float offset

The offset from the current document time, in seconds, at which to begin the елемент.

void endElement()

Creates an end instance time for the current time. The new instance time is added to the end instance times list. The behavior of this method is equivalent to endElementAt(0).

void endElementAt(in float offset)

Creates a end instance time for the current time plus the specified offset. The new instance time is added to the end instance times list.

Parameters

float offset

offset from the current document time, in seconds, at which to end the елемент.

For the corresponding Java binding, see section 6.4 of SMIL Animation [SMILANIM].

19.4.2 Інтерфейс TimeEvent

The TimeEvent interface, defined in SMIL Animation: Supported interfaces, provides specific contextual information associated with Time events.

The different types of events that can occur are:

beginEvent

This event is raised when the елемент local timeline begins to play. It will be raised each time the елемент begins the active duration (i.e. when it restarts, but not when it repeats). It may be raised both in the course of normal (i.e. scheduled or interactive) timeline play, as well as in the case that the елемент was begun with the beginElement or beginElementAt methods. Note that if an елемент is restarted while it is currently playing, the елемент will raise an end event and another begin event, as the елемент restarts.

Bubbles: No
Cancelable: No
Context Info: None

endEvent

This event is raised at the active end of the елемент. Note that this event is not raised at the simple end of each repeat. This event may be raised both in the course of normal (i.e. scheduled or interactive) timeline play, as well as in the case that the елемент was ended with the endElement or endElementAt methods. Note that if an елемент is restarted while it is currently playing, the елемент will raise an end event and another begin event, as the елемент restarts.

Bubbles: No
Cancelable: No
Context Info: None

repeatEvent

This event is raised when an елемент local timeline repeats. It will be raised each time the елемент repeats, after the first iteration.
The event provides a numerical indication of which repeat iteration is beginning. The value is a 0-based integer, but the repeat event is not raised for the first iteration and so the observed values of the detail атрибут will be >= 1.

Bubbles: No
Cancelable: No
Context Info: detail (current iteration)

interface TimeEvent : Event {

  readonly атрибут AbstractView view;
  readonly атрибут long detail;

  void initTimeEvent(in DOMString typeArg, in AbstractView viewArg, in long detailArg);
};

Attributes:

view (readonly AbstractView): The view атрибут identifies the AbstractView [DOM2VIEWS] from which the event was generated.
detail (readonly long): Specifies some detail information about the Event, depending on the type of the event. For this event type, indicates the repeat number for the animation.

Operations:

void initTimeEvent(in DOMString typeArg, in AbstractView viewArg, in long detailArg)

The initTimeEvent method is used to initialize the value of a TimeEvent created through the DocumentEvent interface. This method may only be called before the TimeEvent has been dispatched via the dispatchEvent method, though it may be called multiple times during that phase if necessary. If called multiple times, the final invocation takes precedence.

Parameters

DOMString typeArg

Specifies the event type.
AbstractView viewArg

Specifies the Event's AbstractView.
long detailArg

Specifies the Event's detail.

For the corresponding Java binding, see section 6.4 of SMIL Animation [SMILANIM].

19.4.3 Інтерфейс SVGAnimationElement

The SVGAnimationElement interface is the base interface for all of the animation елемент interfaces: SVGAnimateElement, SVGSetElement, SVGAnimateColorElement, SVGAnimateMotionElement and SVGAnimateTransformElement.

Unlike other SVG DOM interfaces, the SVG DOM does not specify convenience DOM властивості corresponding to the various language атрибути on SVG's animation елементи. Specification of these convenience властивості in a way that will be compatible with future versions of SMIL Animation is expected in a future version of SVG. The current method for accessing and modifying the атрибути on the animation елементи is to use the standard getAttribute, setAttribute, getAttributeNS and setAttributeNS defined in DOM Level 2 Core [DOM2].

interface SVGAnimationElement : SVGElement,
                                SVGTests,
                                SVGExternalResourcesRequired,
                                ElementTimeControl {

  readonly атрибут SVGElement targetElement;

  float getStartTime() raises(DOMException);
  float getCurrentTime();
  float getSimpleDuration() raises(DOMException);
};

Attributes:

targetElement (readonly SVGElement): The елемент which is being animated.

Operations:

float getStartTime()

Returns the begin time, in seconds, for this animation елемент's current interval, if it exists, regardless of whether the interval has begun yet. If there is no current interval, then a DOMException with code INVALID_STATE_ERR is thrown.

Returns

The start time, in seconds, of this animation елемент's current interval.

Exceptions

DOMException, code INVALID_STATE_ERR: The animation елемент does not have a current interval.

float getCurrentTime()

Returns the current time in seconds relative to time zero for the given time container.

Returns: The current time in seconds relative to time zero for the given time container.

float getSimpleDuration()

Returns the number of seconds for the simple duration for this animation. If the simple duration is undefined (e.g., the end time is indefinite), then an exception is raised.

Returns

number of seconds for the simple duration for this animation.

Exceptions

DOMException, code NOT_SUPPORTED_ERR: The simple duration is not determined on the given елемент.

19.4.4 Інтерфейс SVGAnimateElement

The SVGAnimateElement interface corresponds to the ‘animate’ елемент.

Object-oriented access to the атрибути of the ‘animate’ елемент via the SVG DOM is not available.

interface SVGAnimateElement : SVGAnimationElement,
                              SVGStylable {
};

19.4.5 Інтерфейс SVGSetElement

The SVGSetElement interface corresponds to the ‘set’ елемент.

Object-oriented access to the атрибути of the ‘set’ елемент via the SVG DOM is not available.

interface SVGSetElement : SVGAnimationElement {
};

19.4.6 Інтерфейс SVGAnimateMotionElement

The SVGAnimateMotionElement interface corresponds to the ‘animateMotion’ елемент.

Object-oriented access to the атрибути of the ‘animateMotion’ елемент via the SVG DOM is not available.

interface SVGAnimateMotionElement : SVGAnimationElement {
};

19.4.7 Інтерфейс SVGMPathElement

The SVGMPathElement interface corresponds to the ‘mpath’ елемент.

interface SVGMPathElement : SVGElement,
                            SVGURIReference,
                            SVGExternalResourcesRequired {
};

19.4.8 Інтерфейс SVGAnimateColorElement

The SVGAnimateColorElement interface corresponds to the ‘animateColor’ елемент.

Object-oriented access to the атрибути of the ‘animateColor’ елемент via the SVG DOM is not available.

interface SVGAnimateColorElement : SVGAnimationElement,
                                   SVGStylable {
};

19.4.9 Інтерфейс SVGAnimateTransformElement

The SVGAnimateTransformElement interface corresponds to the ‘animateTransform’ елемент.

Object-oriented access to the атрибути of the ‘animateTransform’ елемент via the SVG DOM is not available.

interface SVGAnimateTransformElement : SVGAnimationElement {
};

20 Fonts

20.1 Вступ
20.2 Огляд of SVG fonts
20.3 The ‘font’ елемент
20.4 The ‘glyph’ елемент
20.5 The ‘missing-glyph’ елемент
20.6 Glyph selection rules
20.7 The ‘hkern’ and ‘vkern’ елементи
20.8 Describing a font
20.9 DOM interfaces

20.1 Вступ

Reliable delivery of fonts is a requirement for SVG. Designers need to create SVG content with arbitrary fonts and know that the same graphical result will appear when the content is viewed by all end users, even when end users do not have the necessary fonts installed on their computers. This parallels the print world, where the designer uses a given font when authoring a drawing for print, and the graphical content appears exactly the same in the printed version as it appeared on the designer's authoring system.

SVG utilizes the WebFonts facility defined in CSS2 ([CSS2], section 15.1) as a key mechanism for reliable delivery of font data to end users. In a common scenario, SVG authoring applications generate compressed, subsetted WebFonts for all text елементи used by a given SVG document fragment. Typically, the WebFonts are saved in a location relative to the referencing document.

One disadvantage to the WebFont facility to date is that specifications such as CSS2 do not require support of particular font formats. The result is that different implementations support different Web font formats, thereby making it difficult for Web site creators to post a single Web site using WebFonts that work across all user agents.

To provide a common font format for SVG that is guaranteed to be supported by all conforming SVG viewers, SVG provides a facility to define fonts in SVG. This facility is called SVG fonts.

SVG fonts can improve the semantic richness of graphics that represent text. For example, many company logos consist of the company name drawn artistically. In some cases, accessibility may be enhanced by expressing the logo as a series of glyphs in an SVG font and then rendering the logo as a ‘text’ елемент which references this font.

20.2 Огляд of SVG fonts

An SVG font is a font defined using SVG's ‘font’ елемент.

The purpose of SVG fonts is to allow for delivery of glyph outlines in display-only environments. SVG fonts that accompany Web pages must be supported only in browsing and viewing situations. Graphics editing applications or file translation tools must not attempt to convert SVG fonts into system fonts. The intent is that SVG files be interchangeable between two content creators, but not the SVG fonts that might accompany these SVG files. Instead, each content creator will need to license the given font before being able to successfully edit the SVG file. The ‘font-face-name’ елемент indicates the name of licensed font to use for editing.

SVG fonts contain unhinted font outlines. Because of this, on many implementations there will be limitations regarding the quality and legibility of text in small font sizes. For increased quality and legibility in small font sizes, content creators may want to use an alternate font technology, such as fonts that ship with operating systems or an alternate WebFont format.

Because SVG fonts are expressed using SVG елементи and атрибути, in some cases the SVG font will take up more space than if the font were expressed in a different WebFont format which was especially designed for compact expression of font data. For the fastest delivery of Web pages, content creators may want to use an alternate font technology.

A key value of SVG fonts is guaranteed availability in SVG user agents. In some situations, it might be appropriate for an SVG font to be the first choice for rendering some text. In other situations, the SVG font might be an alternate, back-up font in case the first choice font (perhaps a hinted system font) is not available to a given user.

The characteristics and атрибути of SVG fonts correspond closely to the font characteristics and parameters described in the Fonts chapter of the Cascading Style Sheets (CSS) level 2 specification ([CSS2], chapter 15). In this модель, various font metrics, such as advance values and baseline locations, and the glyph outlines themselves, are expressed in units that are relative to an abstract square whose height is the intended distance between lines of type in the same type size. This square is called the em square and it is the design grid on which the glyph outlines are defined. The value of the ‘units-per-em’ атрибут on the ‘font-face’ елемент specifies how many units the em square is divided into. Common values for other font types are, for example, 250 (Intellifont), 1000 (Type 1) and 2048 (TrueType, TrueType GX and Open-Type). Unlike standard graphics in SVG, where the initial coordinate system has the y-axis pointing downward (see The initial coordinate system), the design grid for SVG fonts, along with the initial coordinate system for the glyphs, has the y-axis pointing upward for consistency with accepted industry practice for many popular font formats.

SVG fonts and their associated glyphs do not specify bounding box information. Because the glyph outlines are expressed as SVG graphics елементи, the implementation has the option to render the glyphs either using standard graphics calls or by using special-purpose font rendering technology, in which case any necessary maximum bounding box and overhang calculations can be performed from analysis of the graphics елементи contained within the glyph outlines.

An SVG font can be either embedded within the same document that uses the font or saved as part of an external resource.

Here is an example of how you might embed an SVG font inside of an SVG document.

<?xml version="1.0" standalone="yes"?>
<svg width="400px" height="300px" version="1.1"
  xmlns = 'http://www.w3.org/2000/svg'>
  <defs>
    <font id="Font1" horiz-adv-x="1000">
      <font-face font-family="Super Sans" font-weight="bold" font-style="normal"
          units-per-em="1000" cap-height="600" x-height="400"
          ascent="700" descent="300"
          alphabetic="0" mathematical="350" ideographic="400" hanging="500">
        <font-face-src>
          <font-face-name name="Super Sans Bold"/>
        </font-face-src>
      </font-face>
      <missing-glyph><path d="M0,0h200v200h-200z"/></missing-glyph>
      <glyph unicode="!" horiz-adv-x="300"><!-- Outline of exclam. pt. glyph --></glyph>
      <glyph unicode="@"><!-- Outline of @ glyph --></glyph>
      <!-- more glyphs -->
    </font>
  </defs>
  <text x="100" y="100" 
           style="font-family: 'Super Sans', Helvetica, sans-serif;
                  font-weight: bold; font-style: normal">Text 
    using embedded font</text>
</svg>

Here is an example of how you might use the CSS @font-face facility ([CSS2], section 15.3.1) to reference an SVG font which is saved in an external file. First referenced SVG font file:

<?xml version="1.0" standalone="yes"?>
<svg width="100%" height="100%" version="1.1"
 xmlns = 'http://www.w3.org/2000/svg'>
  <defs>
    <font id="Font2" horiz-adv-x="1000">
      <font-face font-family="Super Sans" font-weight="normal" font-style="italic"
          units-per-em="1000" cap-height="600" x-height="400"
          ascent="700" descent="300"
          alphabetic="0" mathematical="350" ideographic="400" hanging="500">
        <font-face-src>
          <font-face-name name="Super Sans Italic"/>
        </font-face-src>
      </font-face>
      <missing-glyph><path d="M0,0h200v200h-200z"/></missing-glyph>
      <glyph unicode="!" horiz-adv-x="300"><!-- Outline of exclam. pt. glyph --></glyph>
      <glyph unicode="@"><!-- Outline of @ glyph --></glyph>
      <!-- more glyphs -->
    </font>
  </defs>
</svg>

The SVG file which uses/references the above SVG font

<?xml version="1.0" standalone="yes"?>
<svg width="400px" height="300px" version="1.1"
 xmlns = 'http://www.w3.org/2000/svg'>  
  <defs>
    <style type="text/css">
      <![CDATA[
        @font-face {
          font-family: 'Super Sans'; 
          font-weight: normal;
          font-style: italic;
          src: url("myfont.svg#Font2") format("svg")
        }
      ]]>
   </style>
  </defs>
  <text x="100" y="100"
           style="font-family: 'Super Sans'; font-weight:normal;
                  font-style: italic">Text using referenced font</text>
</svg>

20.3 The ‘font’ елемент

The ‘font’ елемент defines an SVG font.

‘font’

Categories:

None

Content модель:

Any number of the following елементи, in any order:

descriptive елементи — ‘desc’, ‘metadata’, ‘title’
‘font-face’
‘glyph’
‘hkern’
‘missing-glyph’
‘vkern’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘externalResourcesRequired’
‘horiz-origin-x’
‘horiz-origin-y’
‘horiz-adv-x’
‘vert-origin-x’
‘vert-origin-y’
‘vert-adv-y’

DOM Інтерфейсs:

SVGFontElement

Attribute definitions:

horiz-origin-x = "<number>": The X-coordinate in the font coordinate system of the origin of a glyph to be used when drawing horizontally oriented text. (Note that the origin applies to all glyphs in the font.)
If the атрибут is not specified, the effect is as if a value of '0' were specified.
Animatable: no.
horiz-origin-y = "<number>": The Y-coordinate in the font coordinate system of the origin of a glyph to be used when drawing horizontally oriented text. (Note that the origin applies to all glyphs in the font.)
If the атрибут is not specified, the effect is as if a value of '0' were specified.
Animatable: no.
horiz-adv-x = "<number>": The default horizontal advance after rendering a glyph in horizontal orientation. Glyph widths are required to be non-negative, even if the glyph is typically rendered right-to-left, as in Hebrew and Arabic scripts.
Animatable: no.
vert-origin-x = "<number>": The default X-coordinate in the font coordinate system of the origin of a glyph to be used when drawing vertically oriented text.
If the атрибут is not specified, the effect is as if the атрибут were set to half of the effective value of атрибут ‘horiz-adv-x’.
Animatable: no.
vert-origin-y = "<number>": The default Y-coordinate in the font coordinate system of the origin of a glyph to be used when drawing vertically oriented text.
If the атрибут is not specified, the effect is as if the атрибут were set to the position specified by the font's ‘ascent’ атрибут.
Animatable: no.
vert-adv-y = "<number>": The default vertical advance after rendering a glyph in vertical orientation.
If the атрибут is not specified, the effect is as if a value equivalent of one em were specified (see ‘units-per-em’).
Animatable: no.

Each ‘font’ елемент must have a ‘font-face’ child елемент which describes various characteristics of the font.

20.4 The ‘glyph’ елемент

The ‘glyph’ елемент defines the graphics for a given glyph. The coordinate system for the glyph is defined by the various атрибути in the ‘font’ елемент.

The graphics that make up the ‘glyph’ can be a single path data specification within the ‘d’ атрибут, arbitrary SVG as content within the ‘glyph’, or both. These two alternatives are processed differently (see below).

‘glyph’

Categories:

Content модель:

Any number of the following елементи, in any order:

animation елементи — ‘animate’, ‘animateColor’, ‘animateMotion’, ‘animateTransform’, ‘set’
descriptive елементи — ‘desc’, ‘metadata’, ‘title’
shape елементи — ‘circle’, ‘ellipse’, ‘line’, ‘path’, ‘polygon’, ‘polyline’, ‘rect’
structural елементи — ‘defs’, ‘g’, ‘svg’, ‘symbol’, ‘use’
gradient елементи — ‘linearGradient’, ‘radialGradient’
‘a’
‘altGlyphDef’
‘clipPath’
‘color-profile’
‘cursor’
‘filter’
‘font’
‘font-face’
‘foreignObject’
‘image’
‘marker’
‘mask’
‘pattern’
‘script’
‘style’
‘switch’
‘text’
‘view’

Attributes:

core атрибути — ‘id’, ‘xml:base’, ‘xml:lang’, ‘xml:space’
presentation атрибути — ‘alignment-baseline’, ‘baseline-shift’, ‘clip’, ‘clip-path’, ‘clip-rule’, ‘color’, ‘color-interpolation’, ‘color-interpolation-filters’, ‘color-profile’, ‘color-rendering’, ‘cursor’, ‘direction’, ‘display’, ‘dominant-baseline’, ‘enable-background’, ‘fill’, ‘fill-opacity’, ‘fill-rule’, ‘filter’, ‘flood-color’, ‘flood-opacity’, ‘font-family’, ‘font-size’, ‘font-size-adjust’, ‘font-stretch’, ‘font-style’, ‘font-variant’, ‘font-weight’, ‘glyph-orientation-horizontal’, ‘glyph-orientation-vertical’, ‘image-rendering’, ‘kerning’, ‘letter-spacing’, ‘lighting-color’, ‘marker-end’, ‘marker-mid’, ‘marker-start’, ‘mask’, ‘opacity’, ‘overflow’, ‘pointer-events’, ‘shape-rendering’, ‘stop-color’, ‘stop-opacity’, ‘stroke’, ‘stroke-dasharray’, ‘stroke-dashoffset’, ‘stroke-linecap’, ‘stroke-linejoin’, ‘stroke-miterlimit’, ‘stroke-opacity’, ‘stroke-width’, ‘text-anchor’, ‘text-decoration’, ‘text-rendering’, ‘unicode-bidi’, ‘visibility’, ‘word-spacing’, ‘writing-mode’
‘class’
‘style’
‘d’
‘horiz-adv-x’
‘vert-origin-x’
‘vert-origin-y’
‘vert-adv-y’
‘unicode’
‘glyph-name’
‘orientation’
‘arabic-form’
‘lang’

DOM Інтерфейсs:

SVGGlyphElement

Attribute definitions:

unicode = "<string>": One or more Unicode characters indicating the sequence of Unicode characters which corresponds to this glyph. If a character is provided, then this glyph corresponds to the given Unicode character. If multiple characters are provided, then this glyph corresponds to the given sequence of Unicode characters. One use of a sequence of characters is ligatures. For example, if unicode="ffl", then the given glyph will be used to render the sequence of characters "f", "f", and "l".

It is often useful to refer to characters using XML character references expressed in hexadecimal notation or decimal notation. For example, unicode="ffl" could be expressed as XML character references in hexadecimal notation as unicode="ffl" or in decimal notation as unicode="ffl".

The ‘unicode’ атрибут contributes to the process for deciding which glyph(s) are used to represent which character(s). See glyph selection rules. If the ‘unicode’ атрибут is not provided for a given ‘glyph’, then the only way to use this glyph is via an ‘altGlyph’ reference.
Animatable: no.
glyph-name = "<name> [, <name> ]* ": A name for the glyph. It is recommended that glyph names be unique within a font. The glyph names can be used in situations where Unicode character numbers do not provide sufficient information to access the correct glyph, such as when there are multiple glyphs per Unicode character. The glyph names can be referenced in kerning definitions.
Animatable: no.
d = "path data": The definition of the outline of a glyph, using the same syntax as for the ‘d’ атрибут on a ‘path’ елемент. See Path data.
See below for a discussion of this атрибут.
Animatable: no.
orientation = "h | v": Indicates that the given glyph is only to be used for a particular inline-progression-direction (i.e., horizontal or vertical). If the атрибут is not specified, then the glyph can be used in all cases (i.e., both horizontal and vertical inline-progression-direction).
Animatable: no.
arabic-form = "initial | medial | terminal | isolated": For Arabic glyphs, indicates which of the four possible forms this glyph represents.
Animatable: no.
lang = "%LanguageCodes;": The атрибут value is a comma-separated list of language names as defined in BCP 47 [BCP47]. The glyph can be used if the ‘xml:lang’ атрибут exactly matches one of the languages given in the value of this parameter, or if the ‘xml:lang’ атрибут exactly equals a prefix of one of the languages given in the value of this parameter such that the first tag character following the prefix is "-".
Animatable: no.
horiz-adv-x = "<number>": The horizontal advance after rendering the glyph in horizontal orientation. If the атрибут is not specified, the effect is as if the атрибут were set to the value of the font's ‘horiz-adv-x’ атрибут.
Glyph widths are required to be non-negative, even if the glyph is typically rendered right-to-left, as in Hebrew and Arabic scripts.
Animatable: no.
vert-origin-x = "<number>": The X-coordinate in the font coordinate system of the origin of the glyph to be used when drawing vertically oriented text.
If the атрибут is not specified, the effect is as if the атрибут were set to the value of the font's ‘vert-origin-x’ атрибут.
Animatable: no.
vert-origin-y = "<number>": The Y-coordinate in the font coordinate system of the origin of a glyph to be used when drawing vertically oriented text.
If the атрибут is not specified, the effect is as if the атрибут were set to the value of the font's ‘vert-origin-y’ атрибут.
Animatable: no.
vert-adv-y = "<number>": The vertical advance after rendering a glyph in vertical orientation.
If the атрибут is not specified, the effect is as if the атрибут were set to the value of the font's ‘vert-adv-y’ атрибут.
Animatable: no.

The graphics for the ‘glyph’ can be specified using either the ‘d’ атрибут or arbitrary SVG as content within the ‘glyph’.

If the ‘d’ атрибут is specified, then the path data within this атрибут is processed as follows:

Any relative coordinates within the path data specification are converted into equivalent absolute coordinates
Each of these absolute coordinates is transformed from the font coordinate system into the ‘text’ елемент's current coordinate system such that the origin of the font coordinate system is properly positioned and rotated to align with the current text position and orientation for the glyph, and scaled so that the correct ‘font-size’ is achieved.
The resulting, transformed path specification is rendered as if it were a ‘path’ елемент, using the властивості стилю that apply to the characters which correspond to the given glyph, and ignoring any властивості стилю specified on the ‘font’ елемент or the ‘glyph’ елемент.

If the ‘glyph’ has child елементи, then those child елементи are rendered in a manner similar to how the ‘use’ елемент renders a referenced symbol. The rendering effect is as if the contents of the referenced ‘glyph’ елемент were deeply cloned into a separate non-exposed DOM tree. Because the cloned DOM tree is non-exposed, the SVG DOM does not show the cloned instance.

For user agents that support Styling with CSS, the conceptual deep cloning of the referenced ‘glyph’ елемент into a non-exposed DOM tree also copies any властивість values resulting from the CSS cascade ([CSS2], chapter 6) on the referenced ‘glyph’ and its contents, and also applies any властивість values on the ‘font’ елемент. CSS2 selectors can be applied to the original (i.e., referenced) елементи because they are part of the formal document structure. CSS2 selectors cannot be applied to the (conceptually) cloned DOM tree because its contents are not part of the formal document structure.

Property inheritance, however, works as if the referenced ‘glyph’ had been textually included as a deeply cloned child within the document tree. The referenced ‘glyph’ inherits властивості from the елемент that contains the characters that correspond to the ‘glyph’. The ‘glyph’ does not inherit властивості from the ‘font’ елемент's original parents.

In the generated content, for each instance of a given ‘glyph’, a ‘g’ is created which carries with it all властивість values resulting from the CSS cascade on the ‘font’ елемент for the referenced ‘glyph’. Within this ‘g’ is another ‘g’ which carries with it all властивість values resulting from the CSS cascade on the ‘glyph’ елемент. The original contents of the ‘glyph’ елемент are deep-cloned within the inner ‘g’ елемент.

If the ‘glyph’ has both a ‘d’ атрибут and child елементи, the ‘d’ атрибут is rendered first, and then the child елементи.

In general, the ‘d’ атрибут renders in the same manner as system fonts. For example, a dashed pattern will usually look the same if applied to a system font or to an SVG font which defines its glyphs using the ‘d’ атрибут. Many implementations will be able to render glyphs defined with the ‘d’ атрибут quickly and will be able to use a font cache for further performance gains.

Визначення a glyph by including child елементи within the ‘glyph’ gives greater flexibility but more complexity. Different fill and stroke techniques can be used on different parts of the glyphs. For example, the base of an "i" could be red, and the dot could be blue. This approach has an inherent complexity with units. Any властивості specified on a text елементи which represents a length, such as the ‘stroke-width’ властивість, might produce surprising results since the length value will be processed in the coordinate system of the glyph.

20.5 The ‘missing-glyph’ елемент

The ‘missing-glyph’ елемент defines the graphics to use if there is an attempt to draw a glyph from a given font and the given glyph has not been defined. The атрибути on the ‘missing-glyph’ елемент have the same meaning as the corresponding атрибути on the ‘glyph’ елемент.

‘missing-glyph’

Categories: